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Through the Looking-Glass
2010-10-12: Through the Looking-Glass
My radio speaks is binary!
2010-10-10: My radio speaks is binary!
Gigaminx: (present for my birthday)
2010-09-16: Gigaminx: (present for my birthday)
Trini on bike
2010-09-05: Trini on bike
Valporquero
2010-08-28: Valporquero
My new bike!
2010-08-22: My new bike!
Mario and Ana's wedding
2010-08-13: Mario and Ana's wedding
Canyoning in Guara
2010-08-07: Canyoning in Guara
Trini and Mari in Marbella
2010-08-05: Trini and Mari in Marbella
Trini and Chelo in Tabarca
2010-08-03: Trini and Chelo in Tabarca
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Uniform Generator

408.c

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

unsigned int next(unsigned int num, unsigned int step, unsigned int mod)
{
	return ((num+step)%mod);
}

int good_choice(unsigned int step, unsigned int mod)
{
	int num=0;
	int i;

	for(i=0; i<mod-1; i++) {
		num = next(num, step, mod);
		if (num==0) {
			return 0;
		}
	}
	num = next(num, step, mod);
	if (num==0) {
		return 1;
	} else {
		return 0;
	}
}

int main(void)
{
	char buf[1024];
	unsigned int step, mod;

	while(fgets(buf, 1024, stdin)) {
		if (sscanf(buf, "%d %d", &step, &mod)!=2) {
			exit(1);
		}
		if (good_choice(step, mod)) {
			printf("%10d%10d    Good Choice\n\n", step, mod);
		} else {
			printf("%10d%10d    Bad Choice\n\n", step, mod);
		}
	}
	exit(0);
}