malloc分配数组

malloc分配数组

参考链接：

https://zhidao.baidu.com/question/106461194.html

#include <stdio.h>
#include <malloc.h>

int main()
{
    int **a;
    int i, j;
    a = (int**)malloc(sizeof(int*)*3);//为二维数组分配3行
    for (i = 0; i < 3; ++i){//为每列分配4个大小空间
        a[i] = (int*)malloc(sizeof(int)*4);
    }
    //初始化
    for (i = 0; i < 3; ++i){
        for (j = 0; j < 4; ++j){
            a[i][j] = i+j;
        }
    }
    //输出测试
    for (i = 0; i < 3; ++i){
        for (j = 0; j < 4; ++j){
            printf ("%d ", a[i][j]);
        }
        printf ("
");
    }
    //释放动态开辟的空间
    for (i = 0; i < 3; ++i){
        free(a[i]);
    }
    free(a);
    return 0;
}

/*
输出：
0 1 2 3
1 2 3 4
2 3 4 5
*/