C语言如何动态申请空间（一维和二维）

#include <stdio.h>
#include <stdlib.h>
#define M 10000
int main(){
int *a = NULL;
a = (int*)malloc(sizeof(int)*M);  //为a申请int型的空间，其大小为M
printf("申请空间完成\n");
free(a);   //释放空间
system("pause");
return 0;
}

#include <stdio.h>
#include <stdlib.h>
#define M 100
#define N 100

int main()
{
short **a=NULL;
int i;
a = (short**)malloc(sizeof(short*)*M);
for (i = 0; i < M; i++)
{
a[i] = (short*)malloc(sizeof(short) * N);
}
printf("申请空间完成\n");
for (i = 0; i < M; i++)
{
free(a[i]);
}
free(a);
system("pause");
return 0;
}