C | Pointer Basics | Question 7

#include<stdio.h>
int main()
{
   int a;
   char *x;
   x = (char *) &a;
   a = 512;
   x[0] = 1;
   x[1] = 2;
   printf("%d\n",a);
   return 0;
}

What is the output of above program?
(A) Machine dependent
(B) 513
(C) 258
(D) Compiler Error


Answer: (A)

Explanation: Output is 513 in a little endian machine. To understand this output, let integers be stored using 16 bits. In a little endian machine, when we do x[0] = 1 and x[1] = 2, the number a is changed to 00000001 00000010 which is representation of 513 in a little endian machine.

My Personal Notes arrow_drop_up

Save