/**
 * check_pow2: Returns 1 if n is power of 2
 */
#include <stdio.h>
#include <assert.h>

static int check_pow2(unsigned int n) {
  return n != 0 && (n&n-1) == 0;
}

int main(void) {
  assert(!check_pow2(0));
  assert(check_pow2(1));
  assert(check_pow2(2));
  assert(check_pow2(1<<16));
  assert(!check_pow2((1<<16)+1));
  return 0;
}