UVA11971Polygon

//UVA11971Polygon
#include<cstdio>
#include<cstring>
typedef long long LL;
LL Gcd(LL a, LL b) {
    return b == 0 ? a : Gcd(b, a % b);
}
int main() {
	int k, T, kase = 0;
	scanf("%d", &T);
	while(T--) {
		scanf("%*d%d", &k);
		printf("Case #%d: ", ++kase);
		LL a = (LL)((1LL << k) - k - 1);
		LL b = (LL)(1LL << k);
		LL g = Gcd(a, b);
		a /= g; b /= g;
		printf("%lld/%lld\n", a, b);
	}
	return 0;
}
/*
2
1 1
2 2
*/