#include <stdio.h>

unsigned int npot2(unsigned int size)
{
	if (size == 0) return 0;
	unsigned int npot = 1;

	while ((size >>= 1) > 0) {
		npot <<= 1;
	}
	return npot;
}

int main(void)
{
	int i;

	for (i = 0; i < 64; i++)
		printf("n == %d --> %d\n", i, npot2(i));

	return 0;
}

n == 0 --> 0
n == 1 --> 1
n == 2 --> 2
n == 3 --> 2
n == 4 --> 4
n == 5 --> 4
n == 6 --> 4
n == 7 --> 4
n == 8 --> 8
n == 9 --> 8
n == 10 --> 8
n == 11 --> 8
n == 12 --> 8
n == 13 --> 8
n == 14 --> 8
n == 15 --> 8
n == 16 --> 16
n == 17 --> 16
n == 18 --> 16
n == 19 --> 16
n == 20 --> 16
n == 21 --> 16
n == 22 --> 16
n == 23 --> 16
n == 24 --> 16
n == 25 --> 16
n == 26 --> 16
n == 27 --> 16
n == 28 --> 16
n == 29 --> 16
n == 30 --> 16
n == 31 --> 16
n == 32 --> 32
n == 33 --> 32
n == 34 --> 32
n == 35 --> 32
n == 36 --> 32
n == 37 --> 32
n == 38 --> 32
n == 39 --> 32
n == 40 --> 32
n == 41 --> 32
n == 42 --> 32
n == 43 --> 32
n == 44 --> 32
n == 45 --> 32
n == 46 --> 32
n == 47 --> 32
n == 48 --> 32
n == 49 --> 32
n == 50 --> 32
n == 51 --> 32
n == 52 --> 32
n == 53 --> 32
n == 54 --> 32
n == 55 --> 32
n == 56 --> 32
n == 57 --> 32
n == 58 --> 32
n == 59 --> 32
n == 60 --> 32
n == 61 --> 32
n == 62 --> 32
n == 63 --> 32