#include <stdio.h>

unsigned int gcd(unsigned int u, unsigned int v)
{
	int shift;
	if (u == 0) return v;
	if (v == 0) return u;
	shift = __builtin_ctz(u | v);
	u >>= __builtin_ctz(u);
	do {
		v >>= __builtin_ctz(v);
		if (u > v) {
			unsigned int t = v;
			v = u;
			u = t;
		}
		v = v - u;
	} while (v != 0);
	return u << shift;
}


unsigned int is_coprime(unsigned int u, unsigned int v)
{
	if (gcd(u, v) == 1)
		return 1;
	return 0;
}


int main(int argc, char** argv) {
	unsigned int i, j;
	unsigned int coprimes;
	unsigned int MAX_NUM = 1000000;
	int greatest = 0;
	double ratio = 0;

	for (i=1; i<MAX_NUM; i++) {
		if (i % 10000 == 0)
			printf("%i\n", i);

		coprimes = 1;
		for (j = 2; j<i; j++) {
			if (is_coprime(i, j))
				coprimes += 1;
		}

		if (((double)i / coprimes) > greatest) {
			greatest = i;
			ratio = (double)i / coprimes;
		}
	}

	printf("number: %i\n", greatest);
	printf("ratio : %f\n", ratio);
	return 1;
}