Lightoj 1014

I have an Ifter party at the 5^th day of Ramadan for the contestants. For this reason I have invited C contestants and arranged P piaju's (some kind of food, specially made for Ifter). Each contestant ate Q piaju's and L piaju's were left (L < Q).

Now you have to find the number of piaju's each contestant ate.

Input

Input starts with an integer T (≤ 325), denoting the number of test cases.

Each case contains two non-negative integers P and L (0 ≤ L < P < 2³¹).

Output

For each case, print the case number and the number of possible integers in ascending order. If no such integer is found print 'impossible'.

简化问题，求一个数的所有因子。.....sqrt(n)

/* ***********************************************
Author        :guanjun
Created Time  :2016/6/18 22:38:57
File Name     :1014.cpp
************************************************ */
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <iomanip>
#include <list>
#include <deque>
#include <stack>
#define ull unsigned long long
#define ll long long
#define mod 90001
#define INF 0x3f3f3f3f
#define maxn 10010
#define cle(a) memset(a,0,sizeof(a))
const ull inf = 1LL << 61;
const double eps=1e-5;
using namespace std;
priority_queue<int,vector<int>,greater<int> >pq;
struct Node{
    int x,y;
};
struct cmp{
    bool operator()(Node a,Node b){
        if(a.x==b.x) return a.y> b.y;
        return a.x>b.x;
    }
};

bool cmp(int a,int b){
    return a>b;
}
vector<ll>v;
int main()
{
    #ifndef ONLINE_JUDGE
    freopen("in.txt","r",stdin);
    #endif
    //freopen("out.txt","w",stdout);
    int T;
    ll p,l;
    cin>>T;
    for(int t=1;t<=T;t++){
        printf("Case %d: ",t);
        v.clear();
        scanf("%lld %lld",&p,&l);
        ll n=p-l;
        for(ll i=1;i*i<=n;i++){
            if(n%i==0){
                if(i>l)v.push_back(i);
                if(n/i>l&&(i*i!=n))v.push_back(n/i);
            }
        }
        sort(v.begin(),v.end());
        int m=v.size();
        for(int i=0;i<m;i++){
            printf("%lld%c",v[i],i==m-1?10:' ');
        }
        if(m==0)puts("impossible");
    }
    return 0;
}