HDU 5924Mr. Frog’s Problem

One day, you, a clever boy, feel bored in your math class, and then fall asleep without your control. In your dream, you meet Mr. Frog, an elder man. He has a problem for you. 

He gives you two positive integers A and B, and your task is to find all pairs of integers (C, D), such that A≤C≤B,A≤D≤BA≤C≤B,A≤D≤B and AB+BA≤CD+DCAB+BA≤CD+DC

Input

first line contains only one integer T (T≤125T≤125), which indicates the number of test cases. Each test case contains two integers A and B (1≤A≤B≤10181≤A≤B≤1018).

Output

For each test case, first output one line "Case #x:", where x is the case number (starting from 1). 

Then in a new line, print an integer s indicating the number of pairs you find. 

In each of the following s lines, print a pair of integers C and D. pairs should be sorted by C, and then by D in ascending order. 

Sample Input

210 109 27

Sample Output

Case #1:110 10Case #2:29 27
27 9
只有两种情况
#include<cstdio>#include<algorithm>using namespace std;const int N = 1e5 + 10;const int INF = 0x7FFFFFFF;const int mod = 1e9 + 7;int T;long long a, b;int main(){int cas = 1;for (scanf("%d",&T);T--;cas++) {scanf("%lld%lld",&a,&b);printf("Case #%d:\n",cas);if (a==b) {printf("1\n%lld %lld\n",a,b);}else {if (a>b) swap(a,b);printf("2\n%lld %lld\n%lld %lld\n",a,b,b,a);}}return 0;}