C Programming - Memory Allocation - Discussion

Discussion Forum : Memory Allocation - Find Output of Program (Q.No. 6)
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.
Discussion:
24 comments Page 3 of 3.

Sundar said:   1 decade ago
The given answer is exactly correct.

In Turbo C under DOS (16 bit OS), the size of the integer is 2 bytes. So, if you run the above code in Turbo C the output will be 2, 8.

If you run the same code in Linux (32 bit OS) the output will be 4, 16. Because the size of the integer in Linux is 4 bytes.

I have tested in both Turbo C (in DOS) and GCC (in Linux).

I hope this will help you. Have a nice day!

Mohini said:   1 decade ago
in the program ,this
p = (int (*) [MAXCOL])malloc(MAXROW *sizeof(*p));
has no effect in the output.
this will change the value of p,but it will have not change size of p.

Satish Naik said:   1 decade ago
p is a pointer pointing to array of intergers of size 4
As size of integer is 2 bytes then it becomes totally 2*4=8 bytes
i.e sizeof(*p) = 8 bytes

where as
sizeof(p) = 2 bytes as p is integer as holds the address in unsigned integer form.

John said:   1 decade ago
It depends upon the compiler


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