/* roundup2.c : round up a value to next power of 2 
 * PUBLIC DOMAIN - Jon Mayo - December 10, 2008 
 */

#include <stdio.h>
#include <stdlib.h>

/* rounds up n to next power of 2
 * does not do well with n bigger than 0x80000000-1
 */
unsigned roundup2(unsigned n) {
	unsigned s;
	n=abs(n);
	for(s=1;s<32;s<<=1) {
		n|=n>>s;
	}
	return n+1;
}

int main(int argc, char **argv) {
	int i;
	printf("%8s %8s %8s\n", "original", "over", "roundup2");
	for(i=1;i<argc;i++) {
		unsigned n;
		n=strtoul(argv[i], 0, 0);
		printf("%8u %8u %8u\n", n, roundup2(n), roundup2(n-1)); 
	}
	return 0;
}