UPPCL AE 2018:59

Question

Consider the following $\text{C}$ program.

#include<stdio.h>
#define XOR(a, b)  (a) ^ (b)
void func (int *a, int *b)
{
    *a = XOR (*b, *a);
    *b = XOR (*a, *b);
    *a = XOR (*b, *a);
}

main()
{
    int a = 10, b = 20;
    func (&a , &b);
    printf(“%d %d \n”,a,b);
}

What will be the output of the program?

• A. $20 \; 10$
• B. $20 \; 20$
• C. $10 \; 10$
• D. $10 \; 20$