Convert this game of life pattern 26$13b2o$14bo$14bobo$15b2o14$31b2o$30b2o$32bo13$46b2o$45b2o$47bo13$61b 2o$60b2o$62bo4$52b2o$52b2o$71bo$66b2ob3o$66bobobo$68bo$67b2o3$76b2o$ 60b3o12b2o10bobo$52b3o7bo14bo8bo2bo4bo$51bo3bo5bo10b2o11b2o5b2o$50bo5b o15bobo8b2o3bo8b2o$51bo3bo11b2o6bo9b2o10b2o$52b3o8b2obo2bo2bo2bo10bo2b o$52bo2bo7b2o2b2o6bo11bobo$53b3o16bobo$53b2obo15b2o$54bobo$55bo3$52b2o 3b2o$52bobobobo$53b5o$54b3o$55bo7$54b2o$54b2o! to a numpy array. Call the function `rle_to_arr(string, h, w)` which should return a numpy array with .shape (h,w). Fill the array with 1s, and empty with 0.
Convert this game of life pattern 26$13b2o$14bo$14bobo$15b2o14$31b2o$30b2o$32bo13$46b2o$45b2o$47bo13$61b 2o$60b2o$62bo4$52b2o$52b2o$71bo$66b2ob3o$66bobobo$68bo$67b2o3$76b2o$ 60b3o12b2o10bobo$52b3o7bo14bo8bo2bo4bo$51bo3bo5bo10b2o11b2o5b2o$50bo5b o15bobo8b2o3bo8b2o$51bo3bo11b2o6bo9b2o10b2o$52b3o8b2obo2bo2bo2bo10bo2b o$52bo2bo7b2o2b2o6bo11bobo$53b3o16bobo$53b2obo15b2o$54bobo$55bo3$52b2o 3b2o$52bobobobo$53b5o$54b3o$55bo7$54b2o$54b2o! to a numpy array. Call the function `rle_to_arr(string, h, w)` which should return a numpy array with .shape (h,w). Fill the array with 1s, and empty with 0.
To solve this problem, we need to convert a given Run-Length Encoded (RLE) pattern for Conway's Game of Life into a numpy array. The RLE format efficiently represents patterns using counts of consecutive cells (alive or dead) and newlines. The goal is to parse this RLE string and generate a 2D numpy array where alive cells are represented by 1s and dead cells by 0s. ### Approach 1. **Preprocess the RLE String**: Split the input string at the first occurrence of '!' to handle the end of the RLE data correctly. 2. **Parse Tokens**: Convert the RLE string into a list of tokens where each token consists of a count and a symbol ('b' for dead, 'o' for alive, and '$' for newlines). 3. **Initialize the Array**: Create a numpy array of specified dimensions (h, w) initialized to zeros. 4. **Process Tokens**: Iterate through the tokens to populate the numpy array. Track the current row and column, updating them based on the tokens. Handle dead cells by advancing the column count, alive cells by setting the appropriate positions to 1, and newlines by advancing the row count. ### Solution Code
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 | import numpy as np def rle_to_arr(rle_string, h, w): # Split the RLE string at the first '!' to get the pattern rle_part = rle_string.split('!', 1)[0] # Parse the RLE into tokens tokens = [] pos = 0 n = len(rle_part) while pos < n: # Read the count count_str = '' while pos < n and rle_part[pos].isdigit(): count_str += rle_part[pos] pos += 1 count = int(count_str) if count_str else 1 # Read the symbol if pos >= n: break # No more symbols to process symbol = rle_part[pos] pos += 1 if symbol in ['b', 'o', '$']: tokens.append((count, symbol)) # Initialize the array with zeros arr = np.zeros((h, w), dtype=np.uint8) current_row = 0 current_col = 0 for count, symbol in tokens: if current_row >= h: break # No more rows to fill if symbol == 'b': # Advance current column by count (no action needed for zeros) current_col += count elif symbol == 'o': start = current_col end = current_col + count # Ensure we don't exceed the array's width if start < w: end_clamped = min(end, w) if current_row < h: arr[current_row, start:end_clamped] = 1 current_col = end else: current_col = end # Skip beyond the current width elif symbol == '$': # Move to the next row(s) current_row += count current_col = 0 return arr |
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 | import numpy as np def rle_to_arr(rle_string, h, w): # Split the RLE string at the first '!' to get the pattern rle_part = rle_string.split('!', 1)[0] # Parse the RLE into tokens tokens = [] pos = 0 n = len(rle_part) while pos < n: # Read the count count_str = '' while pos < n and rle_part[pos].isdigit(): count_str += rle_part[pos] pos += 1 count = int(count_str) if count_str else 1 # Read the symbol if pos >= n: break # No more symbols to process symbol = rle_part[pos] pos += 1 if symbol in ['b', 'o', '$']: tokens.append((count, symbol)) # Initialize the array with zeros arr = np.zeros((h, w), dtype=np.uint8) current_row = 0 current_col = 0 for count, symbol in tokens: if current_row >= h: break # No more rows to fill if symbol == 'b': # Advance current column by count (no action needed for zeros) current_col += count elif symbol == 'o': start = current_col end = current_col + count # Ensure we don't exceed the array's width if start < w: end_clamped = min(end, w) if current_row < h: arr[current_row, start:end_clamped] = 1 current_col = end else: current_col = end # Skip beyond the current width elif symbol == '$': # Move to the next row(s) current_row += count current_col = 0 return arr |
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 71 72 73 74 75 76 77 78 79 80 81 | import numpy as np def rle_to_arr(rle_string, h, w): # Split the RLE string at the first '!' to get the pattern rle_part = rle_string.split('!', 1)[0] # Parse the RLE into tokens tokens = [] pos = 0 n = len(rle_part) while pos < n: # Read the count count_str = '' while pos < n and rle_part[pos].isdigit(): count_str += rle_part[pos] pos += 1 count = int(count_str) if count_str else 1 # Read the symbol if pos >= n: break # No more symbols to process symbol = rle_part[pos] pos += 1 if symbol in ['b', 'o', '$']: tokens.append((count, symbol)) # Initialize the array with zeros arr = np.zeros((h, w), dtype=np.uint8) current_row = 0 current_col = 0 for count, symbol in tokens: if current_row >= h: break # No more rows to fill if symbol == 'b': # Advance current column by count (no action needed for zeros) current_col += count elif symbol == 'o': start = current_col end = current_col + count # Ensure we don't exceed the array's width if start < w: end_clamped = min(end, w) if current_row < h: arr[current_row, start:end_clamped] = 1 current_col = end else: current_col = end # Skip beyond the current width elif symbol == '$': # Move to the next row(s) current_row += count current_col = 0 return arr answer = (np.array(rle_to_arr(''' 16b2o3b2o$2o$2o$19b2o$17b5o$21bo$17b3o$o16bo$o17b2o$bo16b2o$b2o$3bo$o 17b2o3b2o$2b2o14bobobobo$11bobo5b5o$11b2o7b3o$2o10bo8bo$b2o$b2o2$2o$bo 2$6bobo$2o3bo$bo3bo$o4bo2bo7bo$5b3o7b2o7bo$15bobo5b3o$22b5o$21b2o3b2o$ 22b5o$22b5o$14b2o6bo2bo$14bobo4bo3bo$11b2obobo4bo$11bobobo5bob2o$13bo 8bo$4bobo6b2o$7bo5b3o50bo$7bo5b3o3b2o3b2o40b4o$4bo2bo5b3o3bo5bo41b4o$ 5b3o5b2o35bo16bo2bo$13bo6bo3bo24bobo15b4o4b2o$11bobobo5b3o15b2o7bob2o 14b4o5b2o$11b2obobo21bobo6b2ob2o14bo8b2o$14bobo20bo6b3obob2o$14b2o12b 2o7bo2bo2bo2bo2bobo$28b2o7bo6b2o4bo16bobo$38bobo26b2o$39b2o27bo4b2o$ 21b2o49bo2bo$21b2o28bobo18b3o$52b2o21b2o$52bo21bo$74b2o$59bo$62bo$59bo 14bo$62bo$61bob3o8bo$59b4o2bo9b2o$64bo$52bo$51b2o$40b2o8b2o4b2o5bo$40b 2o7b3o4b2o3bobo$50b2o4b2o2bobo11b2o$4bobo44b2o6bo2bo11b2o$7bo44bo7bobo $o6bo53bobo$o3bo2bo55bo$5b3o5$4b4o$3bo3bo$7bo$3bo2bo3$o2b3o2b2o$2b5o2b o64b3o$9o67bo$9b3o63bo$o7bo2bo$9b2o3$4b2o$o3b3o$o5b2obo5b2o$bo4bo2bo5b 2o$2o4b2obo$o3b3o$4b2o2$59b3o12b2o$61bo12b2o! ''', 101, 77),dtype=np.uint32).flatten() * np.arange(77*101)).sum() expected = 1563304 assert answer == expected, f'Wrong answer; got {answer} instead of {expected}' print('All tests passed') |
All tests passed
Testing if the previous output contains the string All tests passed: True