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C Programming - Memory Allocation

Exercise : Memory Allocation - Find Output of Program
6.
Assume integer is 2 bytes wide. What will be the output of the following code? 
#include<stdio.h>
#include<stdlib.h>
#define MAXROW 3
#define MAXCOL 4

int main()
{
    int (*p)[MAXCOL];
    p = (int (*) [MAXCOL])malloc(MAXROW *sizeof(*p));
    printf("%d, %d\n", sizeof(p), sizeof(*p));
    return 0;
}
2, 8
4, 16
8, 24
16, 32
Answer: Option
Explanation:
No answer description is available. Let's discuss.
7.
How many bytes of memory will the following code reserve? 
#include<stdio.h>
#include<stdlib.h>

int main()
{
    int *p;
    p = (int *)malloc(256 * 256);
    if(p == NULL)
        printf("Allocation failed");
    return 0;
}
65536
Allocation failed
Error
No output
Answer: Option
Explanation:

Hence 256*256 = 65536 is passed to malloc() function which can allocate upto 65535. So the memory allocation will be failed in 16 bit platform (Turbo C in DOS).

If you compile the same program in 32 bit platform like Linux (GCC Compiler) it may allocate the required memory.

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