I have setup the docker container to run the model evaluation.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Sure, here's a Rust program that reads a text file located at `/tmp/file.txt`, processes it in parallel using 4 threads, and prints out the word count as JSON dictionaries for each chunk of the file:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | use std::fs::File; use std::io::{BufReader, Read}; use std::collections::HashMap; use std::sync::{Arc, Mutex}; use std::thread; fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Cannot open file"); let metadata = file.metadata().expect("Cannot read metadata"); let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let reader = BufReader::new(file); let buffer = Arc::new(Mutex::new(reader)); for i in 0..4 { let buffer = Arc::clone(&buffer); let handle = thread::spawn(move || { let mut local_buffer = vec![0; chunk_size]; let start_index = i * chunk_size; let mut word_count = HashMap::new(); { let mut reader = buffer.lock().unwrap(); reader.seek_relative(start_index as i64).expect("Seek failed"); reader.read_exact(&mut local_buffer).expect("Read failed"); } let text = String::from_utf8_lossy(&local_buffer); for word in text.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } let mut json_output = String::from("{"); for (word, count) in word_count { json_output.push_str(&format!("\"{}\": {}, ", word, count)); } if json_output.len() > 1 { json_output.pop(); json_output.pop(); } json_output.push('}'); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().expect("Thread failed"); } } |
1 2 | rustc rust_word_count.rs ./rust_word_count |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | use std::fs::File; use std::io::{BufReader, Read}; use std::collections::HashMap; use std::sync::{Arc, Mutex}; use std::thread; fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Cannot open file"); let metadata = file.metadata().expect("Cannot read metadata"); let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let reader = BufReader::new(file); let buffer = Arc::new(Mutex::new(reader)); for i in 0..4 { let buffer = Arc::clone(&buffer); let handle = thread::spawn(move || { let mut local_buffer = vec![0; chunk_size]; let start_index = i * chunk_size; let mut word_count = HashMap::new(); { let mut reader = buffer.lock().unwrap(); reader.seek_relative(start_index as i64).expect("Seek failed"); reader.read_exact(&mut local_buffer).expect("Read failed"); } let text = String::from_utf8_lossy(&local_buffer); for word in text.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } let mut json_output = String::from("{"); for (word, count) in word_count { json_output.push_str(&format!("\"{}\": {}, ", word, count)); } if json_output.len() > 1 { json_output.pop(); json_output.pop(); } json_output.push('}'); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().expect("Thread failed"); } } |
Below is some student's code. I asked them to parallelize some code. Do not judge if it is correct, I have test cases for that. Logic errors are okay. So are synatx errors. Just tell me if they tried to parallelize it. use std::fs::File; use std::io::{BufReader, Read}; use std::collections::HashMap; use std::sync::{Arc, Mutex}; use std::thread; fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Cannot open file"); let metadata = file.metadata().expect("Cannot read metadata"); let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let reader = BufReader::new(file); let buffer = Arc::new(Mutex::new(reader)); for i in 0..4 { let buffer = Arc::clone(&buffer); let handle = thread::spawn(move || { let mut local_buffer = vec![0; chunk_size]; let start_index = i * chunk_size; let mut word_count = HashMap::new(); { let mut reader = buffer.lock().unwrap(); reader.seek_relative(start_index as i64).expect("Seek failed"); reader.read_exact(&mut local_buffer).expect("Read failed"); } let text = String::from_utf8_lossy(&local_buffer); for word in text.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } let mut json_output = String::from("{"); for (word, count) in word_count { json_output.push_str(&format!("\"{}\": {}, ", word, count)); } if json_output.len() > 1 { json_output.pop(); json_output.pop(); } json_output.push('}'); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().expect("Thread failed"); } } Answer either 'The student passes' or 'The student fails'.
The student passes.
Testing if the previous output contains the string student passes
: True
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 | use std::fs::File; use std::io::{BufReader, Read}; use std::collections::HashMap; use std::sync::{Arc, Mutex}; use std::thread; fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Cannot open file"); let metadata = file.metadata().expect("Cannot read metadata"); let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let reader = BufReader::new(file); let buffer = Arc::new(Mutex::new(reader)); for i in 0..4 { let buffer = Arc::clone(&buffer); let handle = thread::spawn(move || { let mut local_buffer = vec![0; chunk_size]; let start_index = i * chunk_size; let mut word_count = HashMap::new(); { let mut reader = buffer.lock().unwrap(); reader.seek_relative(start_index as i64).expect("Seek failed"); reader.read_exact(&mut local_buffer).expect("Read failed"); } let text = String::from_utf8_lossy(&local_buffer); for word in text.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } let mut json_output = String::from("{"); for (word, count) in word_count { json_output.push_str(&format!("\"{}\": {}, ", word, count)); } if json_output.len() > 1 { json_output.pop(); json_output.pop(); } json_output.push('}'); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().expect("Thread failed"); } } |
{"the": 4, "times,": 2, "age": 2, "best": 1, "foolish": 1, "was": 4, "wisdom,": 1, "worst": 1, "of": 4, "it": 4}
{"way": 1, "had": 1, "before": 1, "the": 1, "us,": 2, "nothing": 1, "direct": 2, "were": 2, "we": 3, "all": 2, "to": 1, "Heaven,": 1, "going": 2, "other": 1}
thread '<unnamed>' panicked at main.rs:30:54:
Read failed: Error { kind: UnexpectedEof, message: "failed to fill whole buffer" }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread '<unnamed>' panicked at main.rs:28:48:
called `Result::unwrap()` on an `Err` value: PoisonError { .. }
thread 'main' panicked at main.rs:53:23:
Thread failed: Any { .. }
Resulting in output: [('Heaven,', 1), ('age', 2), ('all', 2), ('before', 1), ('best', 1), ('direct', 2), ('foolish', 1), ('going', 2), ('had', 1), ('it', 4), ('nothing', 1), ('of', 4), ('other', 1), ('the', 5), ('times,', 2), ('to', 1), ('us,', 2), ('was', 4), ('way', 1), ('we', 3), ('were', 2), ('wisdom,', 1), ('worst', 1)]
Testing if the previous output equals the string [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
: False
I have setup the docker container to run the model evaluation.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Sure, here's a Rust program that reads a text file located at `/tmp/file.txt`, counts the occurrences of each word, and outputs the results as JSON. The program uses multi-threading to divide the work among four threads, each processing approximately one-fourth of the file. Note that we won't use any external crates like `serde_json` for JSON serialization. Here's the complete program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, BufReader, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn word_count(lines: Vec<String>) -> HashMap<String, usize> { let mut counts = HashMap::new(); for line in lines { for word in line.split_whitespace() { *counts.entry(word.to_string()).or_insert(0) += 1; } } counts } fn to_json(counts: &HashMap<String, usize>) -> String { let mut json_str = String::from("{"); for (word, count) in counts { json_str.push_str(&format!("\"{}\": {}, ", word, count)); } if json_str.len() > 1 { json_str.pop(); // Remove the last space json_str.pop(); // Remove the last comma } json_str.push('}'); json_str } fn main() -> io::Result<()> { let file_path = "/tmp/file.txt"; let file = File::open(file_path)?; let metadata = file.metadata()?; let file_size = metadata.len(); let chunk_size = file_size / 4; let file = Arc::new(Mutex::new(file)); let mut handles = vec![]; for i in 0..4 { let file = Arc::clone(&file); let handle = thread::spawn(move || { let mut file = file.lock().unwrap(); file.seek(SeekFrom::Start(i * chunk_size)).unwrap(); let reader = BufReader::new(file.try_clone().unwrap()); let mut lines = vec![]; for line in reader.lines() { if let Ok(line) = line { lines.push(line); } if lines.len() > chunk_size as usize / 100 { break; } } let counts = word_count(lines); let json_output = to_json(&counts); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } Ok(()) } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, BufReader, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn word_count(lines: Vec<String>) -> HashMap<String, usize> { let mut counts = HashMap::new(); for line in lines { for word in line.split_whitespace() { *counts.entry(word.to_string()).or_insert(0) += 1; } } counts } fn to_json(counts: &HashMap<String, usize>) -> String { let mut json_str = String::from("{"); for (word, count) in counts { json_str.push_str(&format!("\"{}\": {}, ", word, count)); } if json_str.len() > 1 { json_str.pop(); // Remove the last space json_str.pop(); // Remove the last comma } json_str.push('}'); json_str } fn main() -> io::Result<()> { let file_path = "/tmp/file.txt"; let file = File::open(file_path)?; let metadata = file.metadata()?; let file_size = metadata.len(); let chunk_size = file_size / 4; let file = Arc::new(Mutex::new(file)); let mut handles = vec![]; for i in 0..4 { let file = Arc::clone(&file); let handle = thread::spawn(move || { let mut file = file.lock().unwrap(); file.seek(SeekFrom::Start(i * chunk_size)).unwrap(); let reader = BufReader::new(file.try_clone().unwrap()); let mut lines = vec![]; for line in reader.lines() { if let Ok(line) = line { lines.push(line); } if lines.len() > chunk_size as usize / 100 { break; } } let counts = word_count(lines); let json_output = to_json(&counts); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } Ok(()) } |
Below is some student's code. I asked them to parallelize some code. Do not judge if it is correct, I have test cases for that. Logic errors are okay. So are synatx errors. Just tell me if they tried to parallelize it. use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, BufReader, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn word_count(lines: Vec<String>) -> HashMap<String, usize> { let mut counts = HashMap::new(); for line in lines { for word in line.split_whitespace() { *counts.entry(word.to_string()).or_insert(0) += 1; } } counts } fn to_json(counts: &HashMap<String, usize>) -> String { let mut json_str = String::from("{"); for (word, count) in counts { json_str.push_str(&format!("\"{}\": {}, ", word, count)); } if json_str.len() > 1 { json_str.pop(); // Remove the last space json_str.pop(); // Remove the last comma } json_str.push('}'); json_str } fn main() -> io::Result<()> { let file_path = "/tmp/file.txt"; let file = File::open(file_path)?; let metadata = file.metadata()?; let file_size = metadata.len(); let chunk_size = file_size / 4; let file = Arc::new(Mutex::new(file)); let mut handles = vec![]; for i in 0..4 { let file = Arc::clone(&file); let handle = thread::spawn(move || { let mut file = file.lock().unwrap(); file.seek(SeekFrom::Start(i * chunk_size)).unwrap(); let reader = BufReader::new(file.try_clone().unwrap()); let mut lines = vec![]; for line in reader.lines() { if let Ok(line) = line { lines.push(line); } if lines.len() > chunk_size as usize / 100 { break; } } let counts = word_count(lines); let json_output = to_json(&counts); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } Ok(()) } Answer either 'The student passes' or 'The student fails'.
The student passes.
Testing if the previous output contains the string student passes
: True
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, BufReader, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn word_count(lines: Vec<String>) -> HashMap<String, usize> { let mut counts = HashMap::new(); for line in lines { for word in line.split_whitespace() { *counts.entry(word.to_string()).or_insert(0) += 1; } } counts } fn to_json(counts: &HashMap<String, usize>) -> String { let mut json_str = String::from("{"); for (word, count) in counts { json_str.push_str(&format!("\"{}\": {}, ", word, count)); } if json_str.len() > 1 { json_str.pop(); // Remove the last space json_str.pop(); // Remove the last comma } json_str.push('}'); json_str } fn main() -> io::Result<()> { let file_path = "/tmp/file.txt"; let file = File::open(file_path)?; let metadata = file.metadata()?; let file_size = metadata.len(); let chunk_size = file_size / 4; let file = Arc::new(Mutex::new(file)); let mut handles = vec![]; for i in 0..4 { let file = Arc::clone(&file); let handle = thread::spawn(move || { let mut file = file.lock().unwrap(); file.seek(SeekFrom::Start(i * chunk_size)).unwrap(); let reader = BufReader::new(file.try_clone().unwrap()); let mut lines = vec![]; for line in reader.lines() { if let Ok(line) = line { lines.push(line); } if lines.len() > chunk_size as usize / 100 { break; } } let counts = word_count(lines); let json_output = to_json(&counts); println!("{}", json_output); }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } Ok(()) } |
{"was": 10, "times,": 2, "everything": 1, "epoch": 2, "it": 10, "the": 11, "worst": 1, "all": 2, "were": 2, "we": 4, "foolishness,": 1, "best": 1, "despair,": 1, "age": 2, "season": 2, "us,": 2, "Light,": 1, "going": 2, "Heaven,": 1, "belief,": 1, "nothing": 1, "other": 1, "incredulity,": 1, "of": 10, "Darkness,": 1, "wisdom,": 1, "direct": 2, "winter": 1, "had": 2, "spring": 1, "to": 1, "before": 2, "hope,": 1, "way": 1}
{"Darkness,": 1, "everything": 1, "incredulity,": 1, "all": 2, "direct": 2, "epoch": 2, "hope,": 1, "were": 2, "before": 2, "us,": 2, "ness,": 1, "Light,": 1, "of": 6, "was": 6, "winter": 1, "had": 2, "Heaven,": 1, "other": 1, "belief,": 1, "season": 2, "nothing": 1, "to": 1, "it": 6, "the": 7, "spring": 1, "way": 1, "despair,": 1, "going": 2, "we": 4}
{"us,": 2, "to": 1, "Heaven,": 1, "season": 1, "e": 1, "was": 2, "everything": 1, "hope,": 1, "other": 1, "we": 4, "had": 2, "it": 2, "of": 3, "nothing": 1, "spring": 1, "all": 2, "direct": 2, "the": 3, "despair,": 1, "before": 2, "way": 1, "going": 2, "were": 2, "winter": 1, "Darkness,": 1}
{"before": 1, "the": 1, "were": 2, "nothing": 1, "us,": 2, "going": 2, "to": 1, "Heaven,": 1, "all": 2, "direct": 2, "other": 1, "had": 1, "way": 1, "we": 3}
Resulting in output: [('Darkness,', 3), ('Heaven,', 4), ('Light,', 2), ('age', 2), ('all', 8), ('before', 7), ('belief,', 2), ('best', 1), ('despair,', 3), ('direct', 8), ('e', 1), ('epoch', 4), ('everything', 3), ('foolishness,', 1), ('going', 8), ('had', 7), ('hope,', 3), ('incredulity,', 2), ('it', 18), ('ness,', 1), ('nothing', 4), ('of', 19), ('other', 4), ('season', 5), ('spring', 3), ('the', 22), ('times,', 2), ('to', 4), ('us,', 8), ('was', 18), ('way', 4), ('we', 15), ('were', 8), ('winter', 3), ('wisdom,', 1), ('worst', 1)]
Testing if the previous output equals the string [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
: False
I have setup the docker container to run the model evaluation.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Certainly! Below is a self-contained Rust program that reads a text file from `/tmp/file.txt`, counts the occurrences of each word, and prints out the result in JSON format. The program uses Rust's standard library and runs in parallel on 4 cores, with each core processing approximately 1/4 of the file. It prints 4 different JSON dictionaries, one per line.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn main() -> io::Result<()> { let path = "/tmp/file.txt"; let file = File::open(path)?; let metadata = file.metadata()?; let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let results = Arc::new(Mutex::new(vec![HashMap::new(), HashMap::new(), HashMap::new(), HashMap::new()])); for i in 0..4 { let path = path.to_string(); let results = Arc::clone(&results); let handle = thread::spawn(move || { let mut file = File::open(path).unwrap(); file.seek(SeekFrom::Start((i * chunk_size) as u64)).unwrap(); let mut reader = io::BufReader::new(file); let mut buffer = String::new(); if i > 0 { // Skip partial word at the start of the chunk reader.read_line(&mut buffer).unwrap(); } buffer.clear(); while buffer.len() < chunk_size && reader.read_line(&mut buffer).unwrap() > 0 {} let words = buffer.split_whitespace().map(String::from); let mut local_count = HashMap::new(); for word in words { *local_count.entry(word).or_insert(0) += 1; } let mut results = results.lock().unwrap(); results[i] = local_count; }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } let results = Arc::try_unwrap(results).unwrap().into_inner().unwrap(); for result in results { print!("{"); let mut first = true; for (word, count) in result { if !first { print!(", "); } first = false; print!("\"{}\": {}", word, count); } println!("}"); } Ok(()) } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn main() -> io::Result<()> { let path = "/tmp/file.txt"; let file = File::open(path)?; let metadata = file.metadata()?; let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let results = Arc::new(Mutex::new(vec![HashMap::new(), HashMap::new(), HashMap::new(), HashMap::new()])); for i in 0..4 { let path = path.to_string(); let results = Arc::clone(&results); let handle = thread::spawn(move || { let mut file = File::open(path).unwrap(); file.seek(SeekFrom::Start((i * chunk_size) as u64)).unwrap(); let mut reader = io::BufReader::new(file); let mut buffer = String::new(); if i > 0 { // Skip partial word at the start of the chunk reader.read_line(&mut buffer).unwrap(); } buffer.clear(); while buffer.len() < chunk_size && reader.read_line(&mut buffer).unwrap() > 0 {} let words = buffer.split_whitespace().map(String::from); let mut local_count = HashMap::new(); for word in words { *local_count.entry(word).or_insert(0) += 1; } let mut results = results.lock().unwrap(); results[i] = local_count; }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } let results = Arc::try_unwrap(results).unwrap().into_inner().unwrap(); for result in results { print!("{"); let mut first = true; for (word, count) in result { if !first { print!(", "); } first = false; print!("\"{}\": {}", word, count); } println!("}"); } Ok(()) } |
Below is some student's code. I asked them to parallelize some code. Do not judge if it is correct, I have test cases for that. Logic errors are okay. So are synatx errors. Just tell me if they tried to parallelize it. use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn main() -> io::Result<()> { let path = "/tmp/file.txt"; let file = File::open(path)?; let metadata = file.metadata()?; let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let results = Arc::new(Mutex::new(vec![HashMap::new(), HashMap::new(), HashMap::new(), HashMap::new()])); for i in 0..4 { let path = path.to_string(); let results = Arc::clone(&results); let handle = thread::spawn(move || { let mut file = File::open(path).unwrap(); file.seek(SeekFrom::Start((i * chunk_size) as u64)).unwrap(); let mut reader = io::BufReader::new(file); let mut buffer = String::new(); if i > 0 { // Skip partial word at the start of the chunk reader.read_line(&mut buffer).unwrap(); } buffer.clear(); while buffer.len() < chunk_size && reader.read_line(&mut buffer).unwrap() > 0 {} let words = buffer.split_whitespace().map(String::from); let mut local_count = HashMap::new(); for word in words { *local_count.entry(word).or_insert(0) += 1; } let mut results = results.lock().unwrap(); results[i] = local_count; }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } let results = Arc::try_unwrap(results).unwrap().into_inner().unwrap(); for result in results { print!("{"); let mut first = true; for (word, count) in result { if !first { print!(", "); } first = false; print!("\"{}\": {}", word, count); } println!("}"); } Ok(()) } Answer either 'The student passes' or 'The student fails'.
The student passes.
Testing if the previous output contains the string student passes
: True
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | use std::collections::HashMap; use std::fs::File; use std::io::{self, BufRead, Seek, SeekFrom}; use std::sync::{Arc, Mutex}; use std::thread; fn main() -> io::Result<()> { let path = "/tmp/file.txt"; let file = File::open(path)?; let metadata = file.metadata()?; let file_size = metadata.len() as usize; let chunk_size = file_size / 4; let mut handles = vec![]; let results = Arc::new(Mutex::new(vec![HashMap::new(), HashMap::new(), HashMap::new(), HashMap::new()])); for i in 0..4 { let path = path.to_string(); let results = Arc::clone(&results); let handle = thread::spawn(move || { let mut file = File::open(path).unwrap(); file.seek(SeekFrom::Start((i * chunk_size) as u64)).unwrap(); let mut reader = io::BufReader::new(file); let mut buffer = String::new(); if i > 0 { // Skip partial word at the start of the chunk reader.read_line(&mut buffer).unwrap(); } buffer.clear(); while buffer.len() < chunk_size && reader.read_line(&mut buffer).unwrap() > 0 {} let words = buffer.split_whitespace().map(String::from); let mut local_count = HashMap::new(); for word in words { *local_count.entry(word).or_insert(0) += 1; } let mut results = results.lock().unwrap(); results[i] = local_count; }); handles.push(handle); } for handle in handles { handle.join().unwrap(); } let results = Arc::try_unwrap(results).unwrap().into_inner().unwrap(); for result in results { print!("{"); let mut first = true; for (word, count) in result { if !first { print!(", "); } first = false; print!("\"{}\": {}", word, count); } println!("}"); } Ok(()) } |
error: invalid format string: expected `'}'` but string was terminated
--> main.rs:58:18
|
58 | print!("{");
| -^ expected `'}'` in format string
| |
| because of this opening brace
|
= note: if you intended to print `{`, you can escape it using `{{`
error: invalid format string: unmatched `}` found
--> main.rs:67:19
|
67 | println!("}");
| ^ unmatched `}` in format string
|
= note: if you intended to print `}`, you can escape it using `}}`
error: aborting due to 2 previous errors
main.sh: line 2: ./a.out: No such file or directory
Resulting in output: []
Testing if the previous output equals the string [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
: False
I have setup the docker container to run the model evaluation.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Sure, here's a self-contained Rust program that reads from `/tmp/file.txt`, splits the work into four threads for parallel processing, and prints out four separate JSON dictionaries representing word counts. Make sure you have Rust installed on your system and compile the program using `rustc`.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 | use std::collections::HashMap; use std::fs::File; use std::io::{BufRead, BufReader}; use std::sync::{Arc, Mutex}; use std::thread; /// Function to count words in a slice of lines fn count_words(lines: &[String]) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for line in lines { for word in line.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } } word_count } /// Function to convert a HashMap to a JSON string fn hashmap_to_json(map: &HashMap<String, usize>) -> String { let mut json = String::from("{"); for (key, value) in map { json.push_str(&format!(r#""{}": {},"#, key, value)); } json.pop(); // Remove the last comma json.push('}'); json } fn main() { // Read the file into a Vec of lines let file = File::open("/tmp/file.txt").expect("Cannot open file"); let reader = BufReader::new(file); let lines: Vec<String> = reader.lines().map(|line| line.unwrap()).collect(); // Split the lines into four chunks for parallel processing let chunk_size = (lines.len() + 3) / 4; // Ensure we don't miss any lines let chunks: Vec<Vec<String>> = lines.chunks(chunk_size).map(|chunk| chunk.to_vec()).collect(); // Shared vector to store results let results = Arc::new(Mutex::new(Vec::new())); let mut handles = vec![]; for chunk in chunks { let results = Arc::clone(&results); let handle = thread::spawn(move || { let word_count = count_words(&chunk); let json = hashmap_to_json(&word_count); let mut results = results.lock().unwrap(); results.push(json); }); handles.push(handle); } // Wait for all threads to finish for handle in handles { handle.join().unwrap(); } // Print results let results = results.lock().unwrap(); for result in results.iter() { println!("{}", result); } } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 | use std::collections::HashMap; use std::fs::File; use std::io::{BufRead, BufReader}; use std::sync::{Arc, Mutex}; use std::thread; /// Function to count words in a slice of lines fn count_words(lines: &[String]) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for line in lines { for word in line.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } } word_count } /// Function to convert a HashMap to a JSON string fn hashmap_to_json(map: &HashMap<String, usize>) -> String { let mut json = String::from("{"); for (key, value) in map { json.push_str(&format!(r#""{}": {},"#, key, value)); } json.pop(); // Remove the last comma json.push('}'); json } fn main() { // Read the file into a Vec of lines let file = File::open("/tmp/file.txt").expect("Cannot open file"); let reader = BufReader::new(file); let lines: Vec<String> = reader.lines().map(|line| line.unwrap()).collect(); // Split the lines into four chunks for parallel processing let chunk_size = (lines.len() + 3) / 4; // Ensure we don't miss any lines let chunks: Vec<Vec<String>> = lines.chunks(chunk_size).map(|chunk| chunk.to_vec()).collect(); // Shared vector to store results let results = Arc::new(Mutex::new(Vec::new())); let mut handles = vec![]; for chunk in chunks { let results = Arc::clone(&results); let handle = thread::spawn(move || { let word_count = count_words(&chunk); let json = hashmap_to_json(&word_count); let mut results = results.lock().unwrap(); results.push(json); }); handles.push(handle); } // Wait for all threads to finish for handle in handles { handle.join().unwrap(); } // Print results let results = results.lock().unwrap(); for result in results.iter() { println!("{}", result); } } |
Below is some student's code. I asked them to parallelize some code. Do not judge if it is correct, I have test cases for that. Logic errors are okay. So are synatx errors. Just tell me if they tried to parallelize it. use std::collections::HashMap; use std::fs::File; use std::io::{BufRead, BufReader}; use std::sync::{Arc, Mutex}; use std::thread; /// Function to count words in a slice of lines fn count_words(lines: &[String]) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for line in lines { for word in line.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } } word_count } /// Function to convert a HashMap to a JSON string fn hashmap_to_json(map: &HashMap<String, usize>) -> String { let mut json = String::from("{"); for (key, value) in map { json.push_str(&format!(r#""{}": {},"#, key, value)); } json.pop(); // Remove the last comma json.push('}'); json } fn main() { // Read the file into a Vec of lines let file = File::open("/tmp/file.txt").expect("Cannot open file"); let reader = BufReader::new(file); let lines: Vec<String> = reader.lines().map(|line| line.unwrap()).collect(); // Split the lines into four chunks for parallel processing let chunk_size = (lines.len() + 3) / 4; // Ensure we don't miss any lines let chunks: Vec<Vec<String>> = lines.chunks(chunk_size).map(|chunk| chunk.to_vec()).collect(); // Shared vector to store results let results = Arc::new(Mutex::new(Vec::new())); let mut handles = vec![]; for chunk in chunks { let results = Arc::clone(&results); let handle = thread::spawn(move || { let word_count = count_words(&chunk); let json = hashmap_to_json(&word_count); let mut results = results.lock().unwrap(); results.push(json); }); handles.push(handle); } // Wait for all threads to finish for handle in handles { handle.join().unwrap(); } // Print results let results = results.lock().unwrap(); for result in results.iter() { println!("{}", result); } } Answer either 'The student passes' or 'The student fails'.
The student passes.
Testing if the previous output contains the string student passes
: True
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 | use std::collections::HashMap; use std::fs::File; use std::io::{BufRead, BufReader}; use std::sync::{Arc, Mutex}; use std::thread; /// Function to count words in a slice of lines fn count_words(lines: &[String]) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for line in lines { for word in line.split_whitespace() { *word_count.entry(word.to_string()).or_insert(0) += 1; } } word_count } /// Function to convert a HashMap to a JSON string fn hashmap_to_json(map: &HashMap<String, usize>) -> String { let mut json = String::from("{"); for (key, value) in map { json.push_str(&format!(r#""{}": {},"#, key, value)); } json.pop(); // Remove the last comma json.push('}'); json } fn main() { // Read the file into a Vec of lines let file = File::open("/tmp/file.txt").expect("Cannot open file"); let reader = BufReader::new(file); let lines: Vec<String> = reader.lines().map(|line| line.unwrap()).collect(); // Split the lines into four chunks for parallel processing let chunk_size = (lines.len() + 3) / 4; // Ensure we don't miss any lines let chunks: Vec<Vec<String>> = lines.chunks(chunk_size).map(|chunk| chunk.to_vec()).collect(); // Shared vector to store results let results = Arc::new(Mutex::new(Vec::new())); let mut handles = vec![]; for chunk in chunks { let results = Arc::clone(&results); let handle = thread::spawn(move || { let word_count = count_words(&chunk); let json = hashmap_to_json(&word_count); let mut results = results.lock().unwrap(); results.push(json); }); handles.push(handle); } // Wait for all threads to finish for handle in handles { handle.join().unwrap(); } // Print results let results = results.lock().unwrap(); for result in results.iter() { println!("{}", result); } } |
{"epoch": 2,"all": 2,"was": 10,"age": 2,"Darkness,": 1,"of": 10,"incredulity,": 1,"had": 2,"season": 2,"times,": 2,"hope,": 1,"to": 1,"despair,": 1,"us,": 2,"nothing": 1,"worst": 1,"were": 2,"Heaven,": 1,"best": 1,"other": 1,"the": 11,"winter": 1,"before": 2,"everything": 1,"direct": 2,"belief,": 1,"way": 1,"it": 10,"we": 4,"going": 2,"spring": 1,"wisdom,": 1,"Light,": 1,"foolishness,": 1}
Resulting in output: [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
Testing if the previous output equals the string [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
: True
I have setup the docker container to run the model evaluation.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Write a self-contained Rust program that prints a JSON output of how often each word appears in a text file located in /tmp/file.txt. So if the file contains "This is is is, an example" then the program should print to stdout. {"This": 1, "is": 2, "is,": 1, "an": 1, "example": 1} Don't import any crates that would require a Cargo.toml file. I'll just compile it with `rustc yourfile.rs` and it should work. The program should be run by calling /path/to/rust_word_count with no arguments. Make it run in parallel on 4 cores at the same time, each job taking ~1/4 of the file. Print out 4 differnt json dicts, one per line. I'll do the merging. Do not import serde_json, write json output from scratch.
Certainly! Below is a self-contained Rust program that reads a text file located at `/tmp/file.txt`, counts the occurrences of each word, and prints four separate JSON dictionaries, one for each quarter of the file. The program uses Rust's standard library for parallelism.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{BufReader, Read}; use std::sync::{Arc, Mutex}; use std::thread; fn process_chunk(content: &str) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for word in content.split_whitespace() { let counter = word_count.entry(word.to_string()).or_insert(0); *counter += 1; } word_count } fn serialize_to_json(word_count: &HashMap<String, usize>) -> String { let mut json_string = String::from("{"); for (i, (word, count)) in word_count.iter().enumerate() { if i > 0 { json_string.push(','); } json_string.push_str(&format!(r#""{}": {}"#, word, count)); } json_string.push('}'); json_string } fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Unable to open file"); let mut reader = BufReader::new(file); let mut content = String::new(); reader.read_to_string(&mut content).expect("Unable to read file"); let len = content.len(); let chunk_size = len / 4; let chunks: Vec<String> = (0..4) .map(|i| { let start = i * chunk_size; let end = if i == 3 { len } else { (i + 1) * chunk_size }; content[start..end].to_string() }) .collect(); let result = Arc::new(Mutex::new(vec![HashMap::new(); 4])); let mut handles = vec![]; for (i, chunk) in chunks.into_iter().enumerate() { let result = Arc::clone(&result); let handle = thread::spawn(move || { let word_count = process_chunk(&chunk); let mut result = result.lock().unwrap(); result[i] = word_count; }); handles.push(handle); } for handle in handles { handle.join().expect("Thread panicked"); } let result = result.lock().unwrap(); for word_count in result.iter() { println!("{}", serialize_to_json(word_count)); } } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{BufReader, Read}; use std::sync::{Arc, Mutex}; use std::thread; fn process_chunk(content: &str) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for word in content.split_whitespace() { let counter = word_count.entry(word.to_string()).or_insert(0); *counter += 1; } word_count } fn serialize_to_json(word_count: &HashMap<String, usize>) -> String { let mut json_string = String::from("{"); for (i, (word, count)) in word_count.iter().enumerate() { if i > 0 { json_string.push(','); } json_string.push_str(&format!(r#""{}": {}"#, word, count)); } json_string.push('}'); json_string } fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Unable to open file"); let mut reader = BufReader::new(file); let mut content = String::new(); reader.read_to_string(&mut content).expect("Unable to read file"); let len = content.len(); let chunk_size = len / 4; let chunks: Vec<String> = (0..4) .map(|i| { let start = i * chunk_size; let end = if i == 3 { len } else { (i + 1) * chunk_size }; content[start..end].to_string() }) .collect(); let result = Arc::new(Mutex::new(vec![HashMap::new(); 4])); let mut handles = vec![]; for (i, chunk) in chunks.into_iter().enumerate() { let result = Arc::clone(&result); let handle = thread::spawn(move || { let word_count = process_chunk(&chunk); let mut result = result.lock().unwrap(); result[i] = word_count; }); handles.push(handle); } for handle in handles { handle.join().expect("Thread panicked"); } let result = result.lock().unwrap(); for word_count in result.iter() { println!("{}", serialize_to_json(word_count)); } } |
Below is some student's code. I asked them to parallelize some code. Do not judge if it is correct, I have test cases for that. Logic errors are okay. So are synatx errors. Just tell me if they tried to parallelize it. use std::collections::HashMap; use std::fs::File; use std::io::{BufReader, Read}; use std::sync::{Arc, Mutex}; use std::thread; fn process_chunk(content: &str) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for word in content.split_whitespace() { let counter = word_count.entry(word.to_string()).or_insert(0); *counter += 1; } word_count } fn serialize_to_json(word_count: &HashMap<String, usize>) -> String { let mut json_string = String::from("{"); for (i, (word, count)) in word_count.iter().enumerate() { if i > 0 { json_string.push(','); } json_string.push_str(&format!(r#""{}": {}"#, word, count)); } json_string.push('}'); json_string } fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Unable to open file"); let mut reader = BufReader::new(file); let mut content = String::new(); reader.read_to_string(&mut content).expect("Unable to read file"); let len = content.len(); let chunk_size = len / 4; let chunks: Vec<String> = (0..4) .map(|i| { let start = i * chunk_size; let end = if i == 3 { len } else { (i + 1) * chunk_size }; content[start..end].to_string() }) .collect(); let result = Arc::new(Mutex::new(vec![HashMap::new(); 4])); let mut handles = vec![]; for (i, chunk) in chunks.into_iter().enumerate() { let result = Arc::clone(&result); let handle = thread::spawn(move || { let word_count = process_chunk(&chunk); let mut result = result.lock().unwrap(); result[i] = word_count; }); handles.push(handle); } for handle in handles { handle.join().expect("Thread panicked"); } let result = result.lock().unwrap(); for word_count in result.iter() { println!("{}", serialize_to_json(word_count)); } } Answer either 'The student passes' or 'The student fails'.
The student passes
Testing if the previous output contains the string student passes
: True
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 | use std::collections::HashMap; use std::fs::File; use std::io::{BufReader, Read}; use std::sync::{Arc, Mutex}; use std::thread; fn process_chunk(content: &str) -> HashMap<String, usize> { let mut word_count = HashMap::new(); for word in content.split_whitespace() { let counter = word_count.entry(word.to_string()).or_insert(0); *counter += 1; } word_count } fn serialize_to_json(word_count: &HashMap<String, usize>) -> String { let mut json_string = String::from("{"); for (i, (word, count)) in word_count.iter().enumerate() { if i > 0 { json_string.push(','); } json_string.push_str(&format!(r#""{}": {}"#, word, count)); } json_string.push('}'); json_string } fn main() { let file_path = "/tmp/file.txt"; let file = File::open(file_path).expect("Unable to open file"); let mut reader = BufReader::new(file); let mut content = String::new(); reader.read_to_string(&mut content).expect("Unable to read file"); let len = content.len(); let chunk_size = len / 4; let chunks: Vec<String> = (0..4) .map(|i| { let start = i * chunk_size; let end = if i == 3 { len } else { (i + 1) * chunk_size }; content[start..end].to_string() }) .collect(); let result = Arc::new(Mutex::new(vec![HashMap::new(); 4])); let mut handles = vec![]; for (i, chunk) in chunks.into_iter().enumerate() { let result = Arc::clone(&result); let handle = thread::spawn(move || { let word_count = process_chunk(&chunk); let mut result = result.lock().unwrap(); result[i] = word_count; }); handles.push(handle); } for handle in handles { handle.join().expect("Thread panicked"); } let result = result.lock().unwrap(); for word_count in result.iter() { println!("{}", serialize_to_json(word_count)); } } |
{"it": 4,"age": 2,"best": 1,"foolish": 1,"times,": 2,"of": 4,"was": 4,"wisdom,": 1,"worst": 1,"the": 4}
{"was": 4,"incredulity,": 1,"season": 1,"th": 1,"it": 4,"epoch": 2,"Light,": 1,"the": 3,"of": 3,"belief,": 1,"ness,": 1}
{"we": 1,"winter": 1,"before": 1,"it": 2,"despair,": 1,"e": 1,"spring": 1,"of": 3,"season": 1,"was": 2,"everything": 1,"Darkness,": 1,"had": 1,"hope,": 1,"the": 2}
{"before": 1,"Heaven,": 1,"all": 2,"other": 1,"us,": 2,"way": 1,"going": 2,"nothing": 1,"to": 1,"had": 1,"the": 1,"were": 2,"direct": 2,"we": 3}
Resulting in output: [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('e', 1), ('epoch', 2), ('everything', 1), ('foolish', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('ness,', 1), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('th', 1), ('the', 10), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
Testing if the previous output equals the string [('Darkness,', 1), ('Heaven,', 1), ('Light,', 1), ('age', 2), ('all', 2), ('before', 2), ('belief,', 1), ('best', 1), ('despair,', 1), ('direct', 2), ('epoch', 2), ('everything', 1), ('foolishness,', 1), ('going', 2), ('had', 2), ('hope,', 1), ('incredulity,', 1), ('it', 10), ('nothing', 1), ('of', 10), ('other', 1), ('season', 2), ('spring', 1), ('the', 11), ('times,', 2), ('to', 1), ('us,', 2), ('was', 10), ('way', 1), ('we', 4), ('were', 2), ('winter', 1), ('wisdom,', 1), ('worst', 1)]
: False