2016CCPC东北-B.Mr. Frog’s Problem

题目链接http://acm.hdu.edu.cn/contests/contest_showproblem.php?pid=1003&cid=729

#include<stdio.h>
#include<iostream>
#define ll long long
using namespace std;
int main(){
    int t;
    cin>>t;
    int cnt=1;
    while(t--){
        ll a,b;
        cin>>a>>b;
        printf("Case #%d:\n",cnt);
        if(a==b){
            printf("1\n");
            printf("%lld %lld\n",a,b);
        }
        else{
            printf("2\n");
            printf("%lld %lld\n",a,b);
            printf("%lld %lld\n",b,a); 
        }
        cnt++;
    }
    return 0;
}