为结构中的二维数组分配内存

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

typedef struct {
    int** data;
    int rows;
    int cols;
} Matrix;

Matrix createMatrix(int rows, int cols) {
    Matrix matrix;

    // 为行指针数组分配内存
    matrix.data = (int**)malloc(rows * sizeof(int*));

    // 为每一行的列元素分配内存
    for (int i = 0; i < rows; i++) {
        matrix.data[i] = (int*)malloc(cols * sizeof(int));
    }

    matrix.rows = rows;
    matrix.cols = cols;

    return matrix;
}

void freeMatrix(Matrix matrix) {
    // 释放每一行的内存
    for (int i = 0; i < matrix.rows; i++) {
        free(matrix.data[i]);
    }

    // 释放行指针数组的内存
    free(matrix.data);
}

int main() {
    int rows = 3;
    int cols = 4;

    Matrix matrix = createMatrix(rows, cols);

    // 对二维数组赋值
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            matrix.data[i][j] = i * cols + j;
        }
    }

    // 打印二维数组
    for (int i = 0; i < rows; i++) {
        for (int j = 0; j < cols; j++) {
            printf("%d ", matrix.data[i][j]);
        }
        printf("\n");
    }

    freeMatrix(matrix);

    return 0;
}