Initial Query

Rewrite this function in C. You can assume that the input is a 2d matrix correctly formatted. Call it rref(int** matrix, int rows, int cols, int graphlen) where the size is matrix[rows][cols]. Return an int** of used_for_row. def rref(matrix, graphlen): PH = 16 extra = 0 col = 0 pivots = [] used_for_row = [set([i]) for i in range(matrix.shape[0])] matrix = matrix%PH while col+extra < matrix.shape[1]-1 and col < matrix.shape[0]: if matrix[col,col+extra] == 0: if np.all(matrix[:,col] == 0): extra += 1 continue other = np.argwhere(matrix[:,col+extra] != 0).flatten()[-1] if other < col: extra += 1 continue matrix[col], matrix[other] = list(matrix[other]), list(matrix[col]) used_for_row[col], used_for_row[other] = used_for_row[other], used_for_row[col] pivots.append(col+extra) pivot = matrix[col,col+extra] if col+extra < graphlen: assert np.abs(pivot) == 1 or np.abs(pivot) == PH-1 else: assert np.abs(pivot) == 2 or np.abs(pivot) == PH-2 pivot //= 2 matrix[col] *= pivot matrix[col] %= PH others = np.argwhere(matrix[:,col+extra]).flatten() for i in others: if i == col: continue used_for_row[i] |= used_for_row[col] if col < graphlen: matrix[i] -= matrix[col]*matrix[i,col+extra] else: while matrix[i,col+extra] != 0: matrix[i] = (matrix[i]-matrix[col])%PH matrix[i] %= PH col += 1 matrix = np.array(matrix)%PH return [sorted(x) for x in used_for_row]

LLM Generation

Query

Rewrite this function in C. You can assume that the input is a 2d matrix correctly formatted. Call it rref(int** matrix, int rows, int cols, int graphlen) where the size is matrix[rows][cols]. Return an int** of used_for_row. def rref(matrix, graphlen): PH = 16 extra = 0 col = 0 pivots = [] used_for_row = [set([i]) for i in range(matrix.shape[0])] matrix = matrix%PH while col+extra < matrix.shape[1]-1 and col < matrix.shape[0]: if matrix[col,col+extra] == 0: if np.all(matrix[:,col] == 0): extra += 1 continue other = np.argwhere(matrix[:,col+extra] != 0).flatten()[-1] if other < col: extra += 1 continue matrix[col], matrix[other] = list(matrix[other]), list(matrix[col]) used_for_row[col], used_for_row[other] = used_for_row[other], used_for_row[col] pivots.append(col+extra) pivot = matrix[col,col+extra] if col+extra < graphlen: assert np.abs(pivot) == 1 or np.abs(pivot) == PH-1 else: assert np.abs(pivot) == 2 or np.abs(pivot) == PH-2 pivot //= 2 matrix[col] *= pivot matrix[col] %= PH others = np.argwhere(matrix[:,col+extra]).flatten() for i in others: if i == col: continue used_for_row[i] |= used_for_row[col] if col < graphlen: matrix[i] -= matrix[col]*matrix[i,col+extra] else: while matrix[i,col+extra] != 0: matrix[i] = (matrix[i]-matrix[col])%PH matrix[i] %= PH col += 1 matrix = np.array(matrix)%PH return [sorted(x) for x in used_for_row]

Output

Here is the C version of the provided function. Note that this function uses dynamic memory allocation for the matrix and the `used_for_row` array. It's the caller's responsibility to free this memory to prevent memory leaks. 

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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

// Function to swap two rows of the matrix
void swap_rows(int** matrix, int row1, int row2, int cols) {
    int* temp = matrix[row1];
    matrix[row1] = matrix[row2];
    matrix[row2] = temp;
}

// Function to reduce the matrix to row echelon form
int** rref(int** matrix, int rows, int cols, int graphlen) {
    const int PH = 16;

    int extra = 0;
    int col = 0;
    int* pivots = (int*) malloc(rows * sizeof(int));
    int pivot_count = 0;

    // Initialize used_for_row
    int** used_for_row = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        used_for_row[i] = (int*) malloc(1 * sizeof(int));
        used_for_row[i][0] = i;
        used_for_row[i][1] = -1; // sentinel value to mark end of array
    }

    // Reduce matrix modulo PH
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    while (col + extra < cols - 1 && col < rows) {
        // Check if pivot is zero
        if (matrix[col][col + extra] == 0) {
            // Check if column is all zeros
            int all_zeros = 1;
            for (int i = 0; i < rows; i++) {
                if (matrix[i][col + extra] != 0) {
                    all_zeros = 0;
                    break;
                }
            }

            if (all_zeros) {
                extra++;
                continue;
            }

            // Find another row with non-zero value in this column
            int other = -1;
            for (int i = rows - 1; i >= 0; i--) {
                if (matrix[i][col + extra] != 0) {
                    other = i;
                    break;
                }
            }

            if (other < col) {
                extra++;
                continue;
            }

            swap_rows(matrix, col, other, cols);
            int* temp = used_for_row[col];
            used_for_row[col] = used_for_row[other];
            used_for_row[other] = temp;

        }

        pivots[pivot_count++] = col + extra;
        int pivot = matrix[col][col + extra];

        // Check pivot value
        if (col + extra < graphlen) {
            assert(abs(pivot) == 1 || abs(pivot) == PH - 1);
        } else {
            assert(abs(pivot) == 2 || abs(pivot) == PH - 2);
            pivot /= 2;
        }

        // Normalize pivot row
        for (int j = 0; j < cols; j++) {
            matrix[col][j] *= pivot;
            matrix[col][j] %= PH;
        }

        // Subtract pivot row from other rows
        for (int i = 0; i < rows; i++) {
            if (i == col) continue;
            if (col < graphlen) {
                for (int j = 0; j < cols; j++) {
                    matrix[i][j] -= matrix[col][j] * matrix[i][col + extra];
                    matrix[i][j] %= PH;
                }
            } else {
                while (matrix[i][col + extra] != 0) {
                    for (int j = 0; j < cols; j++) {
                        matrix[i][j] -= matrix[col][j];
                        matrix[i][j] %= PH;
                    }
                }
            }

            // Update used_for_row
            int* new_row = (int*) malloc((used_for_row[i][0] + 1 + 1) * sizeof(int));
            new_row[0] = used_for_row[i][0] + 1;
            int k = 1;
            for (int j = 1; j <= used_for_row[i][0]; j++) {
                new_row[k++] = used_for_row[i][j];
            }
            new_row[k++] = col;
            new_row[k] = -1; // sentinel value to mark end of array
            free(used_for_row[i]);
            used_for_row[i] = new_row;
        }

        col++;
    }

    // Reduce matrix modulo PH again
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    // Sort used_for_row
    for (int i = 0; i < rows; i++) {
        int* row = used_for_row[i];
        int len = row[0];
        for (int j = 1; j <= len; j++) {
            for (int k = j + 1; k <= len; k++) {
                if (row[j] > row[k]) {
                    int temp = row[j];
                    row[j] = row[k];
                    row[k] = temp;
                }
            }
        }
    }

    return used_for_row;
}

// Example usage
int main() {
    int rows = 3;
    int cols = 4;
    int graphlen = 3;

    // Allocate matrix
    int** matrix = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        matrix[i] = (int*) malloc(cols * sizeof(int));
    }

    // Initialize matrix
    matrix[0][0] = 1;
    matrix[0][1] = 2;
    matrix[0][2] = 3;
    matrix[0][3] = 4;
    matrix[1][0] = 5;
    matrix[1][1] = 6;
    matrix[1][2] = 7;
    matrix[1][3] = 8;
    matrix[2][0] = 9;
    matrix[2][1] = 10;
    matrix[2][2] = 11;
    matrix[2][3] = 12;

    int** used_for_row = rref(matrix, rows, cols, graphlen);

    // Print used_for_row
    for (int i = 0; i < rows; i++) {
        printf("Row %d: ", i);
        for (int j = 1; used_for_row[i][j] != -1; j++) {
            printf("%d ", used_for_row[i][j]);
        }
        printf("\n");
    }

    // Free memory
    for (int i = 0; i < rows; i++) {
        free(matrix[i]);
        free(used_for_row[i]);
    }
    free(matrix);
    free(used_for_row);

    return 0;
}
This code will perform row reduction on the input matrix and return the `used_for_row` array. Note that the `used_for_row` array is a 2D array where each row represents the set of rows used to compute the corresponding row in the reduced matrix. The example usage in the `main` function demonstrates how to use the `rref` function and print the resulting `used_for_row` array.

Extract Code

I extracted the following code from that output: 

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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

// Function to swap two rows of the matrix
void swap_rows(int** matrix, int row1, int row2, int cols) {
    int* temp = matrix[row1];
    matrix[row1] = matrix[row2];
    matrix[row2] = temp;
}

// Function to reduce the matrix to row echelon form
int** rref(int** matrix, int rows, int cols, int graphlen) {
    const int PH = 16;

    int extra = 0;
    int col = 0;
    int* pivots = (int*) malloc(rows * sizeof(int));
    int pivot_count = 0;

    // Initialize used_for_row
    int** used_for_row = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        used_for_row[i] = (int*) malloc(1 * sizeof(int));
        used_for_row[i][0] = i;
        used_for_row[i][1] = -1; // sentinel value to mark end of array
    }

    // Reduce matrix modulo PH
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    while (col + extra < cols - 1 && col < rows) {
        // Check if pivot is zero
        if (matrix[col][col + extra] == 0) {
            // Check if column is all zeros
            int all_zeros = 1;
            for (int i = 0; i < rows; i++) {
                if (matrix[i][col + extra] != 0) {
                    all_zeros = 0;
                    break;
                }
            }

            if (all_zeros) {
                extra++;
                continue;
            }

            // Find another row with non-zero value in this column
            int other = -1;
            for (int i = rows - 1; i >= 0; i--) {
                if (matrix[i][col + extra] != 0) {
                    other = i;
                    break;
                }
            }

            if (other < col) {
                extra++;
                continue;
            }

            swap_rows(matrix, col, other, cols);
            int* temp = used_for_row[col];
            used_for_row[col] = used_for_row[other];
            used_for_row[other] = temp;

        }

        pivots[pivot_count++] = col + extra;
        int pivot = matrix[col][col + extra];

        // Check pivot value
        if (col + extra < graphlen) {
            assert(abs(pivot) == 1 || abs(pivot) == PH - 1);
        } else {
            assert(abs(pivot) == 2 || abs(pivot) == PH - 2);
            pivot /= 2;
        }

        // Normalize pivot row
        for (int j = 0; j < cols; j++) {
            matrix[col][j] *= pivot;
            matrix[col][j] %= PH;
        }

        // Subtract pivot row from other rows
        for (int i = 0; i < rows; i++) {
            if (i == col) continue;
            if (col < graphlen) {
                for (int j = 0; j < cols; j++) {
                    matrix[i][j] -= matrix[col][j] * matrix[i][col + extra];
                    matrix[i][j] %= PH;
                }
            } else {
                while (matrix[i][col + extra] != 0) {
                    for (int j = 0; j < cols; j++) {
                        matrix[i][j] -= matrix[col][j];
                        matrix[i][j] %= PH;
                    }
                }
            }

            // Update used_for_row
            int* new_row = (int*) malloc((used_for_row[i][0] + 1 + 1) * sizeof(int));
            new_row[0] = used_for_row[i][0] + 1;
            int k = 1;
            for (int j = 1; j <= used_for_row[i][0]; j++) {
                new_row[k++] = used_for_row[i][j];
            }
            new_row[k++] = col;
            new_row[k] = -1; // sentinel value to mark end of array
            free(used_for_row[i]);
            used_for_row[i] = new_row;
        }

        col++;
    }

    // Reduce matrix modulo PH again
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    // Sort used_for_row
    for (int i = 0; i < rows; i++) {
        int* row = used_for_row[i];
        int len = row[0];
        for (int j = 1; j <= len; j++) {
            for (int k = j + 1; k <= len; k++) {
                if (row[j] > row[k]) {
                    int temp = row[j];
                    row[j] = row[k];
                    row[k] = temp;
                }
            }
        }
    }

    return used_for_row;
}

// Example usage
int main() {
    int rows = 3;
    int cols = 4;
    int graphlen = 3;

    // Allocate matrix
    int** matrix = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        matrix[i] = (int*) malloc(cols * sizeof(int));
    }

    // Initialize matrix
    matrix[0][0] = 1;
    matrix[0][1] = 2;
    matrix[0][2] = 3;
    matrix[0][3] = 4;
    matrix[1][0] = 5;
    matrix[1][1] = 6;
    matrix[1][2] = 7;
    matrix[1][3] = 8;
    matrix[2][0] = 9;
    matrix[2][1] = 10;
    matrix[2][2] = 11;
    matrix[2][3] = 12;

    int** used_for_row = rref(matrix, rows, cols, graphlen);

    // Print used_for_row
    for (int i = 0; i < rows; i++) {
        printf("Row %d: ", i);
        for (int j = 1; used_for_row[i][j] != -1; j++) {
            printf("%d ", used_for_row[i][j]);
        }
        printf("\n");
    }

    // Free memory
    for (int i = 0; i < rows; i++) {
        free(matrix[i]);
        free(used_for_row[i]);
    }
    free(matrix);
    free(used_for_row);

    return 0;
}

Run Code Interpreter

Running the following program: 

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#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

// Function to swap two rows of the matrix
void swap_rows(int** matrix, int row1, int row2, int cols) {
    int* temp = matrix[row1];
    matrix[row1] = matrix[row2];
    matrix[row2] = temp;
}

// Function to reduce the matrix to row echelon form
int** rref(int** matrix, int rows, int cols, int graphlen) {
    const int PH = 16;

    int extra = 0;
    int col = 0;
    int* pivots = (int*) malloc(rows * sizeof(int));
    int pivot_count = 0;

    // Initialize used_for_row
    int** used_for_row = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        used_for_row[i] = (int*) malloc(1 * sizeof(int));
        used_for_row[i][0] = i;
        used_for_row[i][1] = -1; // sentinel value to mark end of array
    }

    // Reduce matrix modulo PH
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    while (col + extra < cols - 1 && col < rows) {
        // Check if pivot is zero
        if (matrix[col][col + extra] == 0) {
            // Check if column is all zeros
            int all_zeros = 1;
            for (int i = 0; i < rows; i++) {
                if (matrix[i][col + extra] != 0) {
                    all_zeros = 0;
                    break;
                }
            }

            if (all_zeros) {
                extra++;
                continue;
            }

            // Find another row with non-zero value in this column
            int other = -1;
            for (int i = rows - 1; i >= 0; i--) {
                if (matrix[i][col + extra] != 0) {
                    other = i;
                    break;
                }
            }

            if (other < col) {
                extra++;
                continue;
            }

            swap_rows(matrix, col, other, cols);
            int* temp = used_for_row[col];
            used_for_row[col] = used_for_row[other];
            used_for_row[other] = temp;

        }

        pivots[pivot_count++] = col + extra;
        int pivot = matrix[col][col + extra];

        // Check pivot value
        if (col + extra < graphlen) {
            assert(abs(pivot) == 1 || abs(pivot) == PH - 1);
        } else {
            assert(abs(pivot) == 2 || abs(pivot) == PH - 2);
            pivot /= 2;
        }

        // Normalize pivot row
        for (int j = 0; j < cols; j++) {
            matrix[col][j] *= pivot;
            matrix[col][j] %= PH;
        }

        // Subtract pivot row from other rows
        for (int i = 0; i < rows; i++) {
            if (i == col) continue;
            if (col < graphlen) {
                for (int j = 0; j < cols; j++) {
                    matrix[i][j] -= matrix[col][j] * matrix[i][col + extra];
                    matrix[i][j] %= PH;
                }
            } else {
                while (matrix[i][col + extra] != 0) {
                    for (int j = 0; j < cols; j++) {
                        matrix[i][j] -= matrix[col][j];
                        matrix[i][j] %= PH;
                    }
                }
            }

            // Update used_for_row
            int* new_row = (int*) malloc((used_for_row[i][0] + 1 + 1) * sizeof(int));
            new_row[0] = used_for_row[i][0] + 1;
            int k = 1;
            for (int j = 1; j <= used_for_row[i][0]; j++) {
                new_row[k++] = used_for_row[i][j];
            }
            new_row[k++] = col;
            new_row[k] = -1; // sentinel value to mark end of array
            free(used_for_row[i]);
            used_for_row[i] = new_row;
        }

        col++;
    }

    // Reduce matrix modulo PH again
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix[i][j] %= PH;
        }
    }

    // Sort used_for_row
    for (int i = 0; i < rows; i++) {
        int* row = used_for_row[i];
        int len = row[0];
        for (int j = 1; j <= len; j++) {
            for (int k = j + 1; k <= len; k++) {
                if (row[j] > row[k]) {
                    int temp = row[j];
                    row[j] = row[k];
                    row[k] = temp;
                }
            }
        }
    }

    return used_for_row;
}

// Example usage
int __delete_this__main() {
    int rows = 3;
    int cols = 4;
    int graphlen = 3;

    // Allocate matrix
    int** matrix = (int**) malloc(rows * sizeof(int*));
    for (int i = 0; i < rows; i++) {
        matrix[i] = (int*) malloc(cols * sizeof(int));
    }

    // Initialize matrix
    matrix[0][0] = 1;
    matrix[0][1] = 2;
    matrix[0][2] = 3;
    matrix[0][3] = 4;
    matrix[1][0] = 5;
    matrix[1][1] = 6;
    matrix[1][2] = 7;
    matrix[1][3] = 8;
    matrix[2][0] = 9;
    matrix[2][1] = 10;
    matrix[2][2] = 11;
    matrix[2][3] = 12;

    int** used_for_row = rref(matrix, rows, cols, graphlen);

    // Print used_for_row
    for (int i = 0; i < rows; i++) {
        printf("Row %d: ", i);
        for (int j = 1; used_for_row[i][j] != -1; j++) {
            printf("%d ", used_for_row[i][j]);
        }
        printf("\n");
    }

    // Free memory
    for (int i = 0; i < rows; i++) {
        free(matrix[i]);
        free(used_for_row[i]);
    }
    free(matrix);
    free(used_for_row);

    return 0;
}



#include<stdio.h>
#include<stdlib.h>

int main() {

int arr0[] = {1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1};
int arr1[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr2[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -20};
int arr3[] = {0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, -20};
int arr4[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr5[] = {0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr6[] = {0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0};
int arr7[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, -30};
int arr8[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr9[] = {0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, -20};
int arr10[] = {1, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1};
int arr11[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr12[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr13[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -14};
int arr14[] = {0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr15[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, -30};
int arr16[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr17[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr18[] = {0, 0, 0, -1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr19[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -13};
int arr20[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr21[] = {0, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr22[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, -20};
int arr23[] = {0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -10};
int arr24[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr25[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -13};
int arr26[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr27[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -13};
int arr28[] = {0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr29[] = {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr30[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int arr31[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr32[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 0, -10};
int arr33[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -13};
int arr34[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -11};
int arr35[] = {0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -9};
int arr36[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, -20};
int arr37[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -2, -40};
int arr38[] = {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int* arr[] = {arr0, arr1, arr2, arr3, arr4, arr5, arr6, arr7, arr8, arr9, arr10, arr11, arr12, arr13, arr14, arr15, arr16, arr17, arr18, arr19, arr20, arr21, arr22, arr23, arr24, arr25, arr26, arr27, arr28, arr29, arr30, arr31, arr32, arr33, arr34, arr35, arr36, arr37, arr38};
int** got = rref(arr, 39, 49, 37);


int answer = got[3][0]+got[3][1]+got[3][2]+got[3][3]+got[3][4]+got[3][5]+got[3][6];
int expected = 146;
if (answer != expected) {
    printf("Wrong answer; got %d instead of %d.\n", answer, expected);
    exit(1);
}
printf("All tests passed\n");
}
And got the output: munmap_chunk(): invalid pointer main.sh: line 2: 16 Aborted (core dumped) ./a.out

Substring Evaluation

Testing if the previous output contains the string All tests passed: False