#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include<vector>
#include<algorithm>
#include<math.h>
#include<cstring>
#include<map>
#include<set>
#include<string>
using namespace std;
/*int gcd(int a, int b, int &x, int &y) {
	if (a == 0) {
		y = 1;
		x = 0;
		return b;
	}
	int x1, y1;
	int d = gcd(b%a, a,x1,y1);
	y = x1;
	x = y1 - (b / a)*x1;
	return d;
}*/
vector<long long >v;
long long a, b;
int css = 1;
void get_div(long long n) {
	int i;
	for (i = 1; i*i < n ; ++i) {
		if (n%i == 0) {
			if(i>b)
			v.push_back(i);
			if((n / i)>b)
			v.push_back(n / i);
		}
	}
	if (i*i == n&&i>b)
		v.push_back(i);
	sort(v.begin(),v.end());
	printf("Case #%d:", css);
	for (i = 0; i < v.size(); ++i) {
		printf(" %d", v[i]);
	}
		printf("\n");
	v.clear();
	css++;
}
int main() {
	int t;
	cin >> t;
	while (t--) {
		scanf("%lld%lld", &a, &b);
		if (a > b)
			get_div(a - b);
		else if(a==b)
			printf("Case #%d: 0\n", css), ++css;
		else
		{
			printf("Case #%d:\n", css), ++css;
		}
	}
	//system("pause");
}