动态申请一维/二维数组

int N = 10;
int M = 10;
int *a;
a = (int *) malloc(sizeof(int)*N);

int **aa;

aa = (int **) malloc(sizeof(int*)*N);

for(int i=0; i<N; i++)
{
    aa[i] = (int *)malloc(sizeof(int)*M);
}