malloc() allocates memory from the heap and not from the stack.

malloc() returns a float pointer if memory is allocated for storing float's and a double pointer if memory is allocated for storing double's.

Point out the correct statement which correctly allocates memory dynamically for 2D array following program?

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

int main()
{
    int *p, i, j;
    /* Add statement here */
    for(i=0; i<3; i++)
    {
        for(j=0; j<4; j++)
        {
            p[i*4+j] = i;
            printf("%d", p[i*4+j]);
        }
    }
    return 0;
}

Point out the correct statement which correctly free the memory pointed to by 's' and 'p' in the following program?

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

int main()
{
    struct ex
    {
        int i;
        float j;
        char *s
    };
    struct ex *p;
    p = (struct ex *)malloc(sizeof(struct ex));
    p->s = (char*)malloc(20);
    return 0;
}

Which of the following statement is correct prototype of the malloc() function in c ?