CareerCup

Interesting question.

Normally you declare a static array like this:
const int m = 10, n = 12;

int ar[m][n];

But that would not take malloc-ed memory. To take malloc-ed memory you have to have a pointer type. It can be done like this:

const int m=10, n=12;
int (*ar)[m][n] = (int(*)[m][n]) malloc(sizeof(*ar));
//Access elements:
(*ar)[1][2] = 3;
// Free the memory.
free(ar); ar = nullptr;

It would be extremely rare that some one would use such a code construct. But the language allows it.

int ** A = (int**) malloc(m * sizeof(int *));
for(int i =0; i<m; i++)
{
	A[i] = malloc(n * sizeof(int));
}

//You can access each element as A[i][j] now//

a = malloc(mn*sizeof(int));