#include <bits/stdc++.h>
using namespace std;
 
// returns true if n is power of 16
bool checkPowerof16(unsigned n)
{
	/*for(int i = 1; i < INT_MAX; i = i*16)
		cout << bitset<32>(i) << endl;*/
 
	// return true if n is power of 2 and its only
	// set bit is present at (0, 4, 8, 12, ...) position
	return n && !(n & (n - 1)) && !(n & 0xEEEEEEEE);
}
 
int main() 
{
	unsigned n = 256*256*16;
 
	if (checkPowerof16(n))
		cout << n << " is power of 16";
	else 
		cout << n << " is not a power of 16";
 
	return 0;
}

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