#include <iostream>
#include <bitset>
using namespace std;
 
// Function to swap bits are position p and q in integer n
int swap(int n, int p, int q)
{
	// p = 8 - p;
	// q = 8 - q;
 
	// if bits are different at position p and q
	if (((n & (1 << p)) >> p) ^ ((n & (1 << q)) >> q))
	{
		n ^= (1 << p);
		n ^= (1 << q);
	}
	return n;
}
 
int main() 
{
	int n = 31;
	int p = 2, q = 4;
 
	cout << n << " in binary is " << bitset<8>(n) << endl;
	n = swap (n, p, q);
	cout << n << " in binary is " << bitset<8>(n) << endl;
 
	return 0;
}

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