Regionals 2014 Asia

题意：问你A-B 互相 取或   互相 取与  分别值是多少

解题思路：看那些位数不变，那些位数变化

解题代码：

// File Name: b.cpp
// Author: darkdream
// Created Time: 2015年04月04日 星期六 12时22分58秒

#include<vector>
#include<list>
#include<map>
#include<set>
#include<deque>
#include<stack>
#include<bitset>
#include<algorithm>
#include<functional>
#include<numeric>
#include<utility>
#include<sstream>
#include<iostream>
#include<iomanip>
#include<cstdio>
#include<cmath>
#include<cstdlib>
#include<cstring>
#include<ctime>
#define LL long long

using namespace std;
int t;
LL L , R;
int main(){
     scanf("%d",&t);
     for(int CA = 1; CA <= t;CA++)
     {
        scanf("%lld %lld",&L,&R); 
        LL ans1,ans2; 
        ans1 = ans2 = 0  ;
        LL i ; 
        for(i = 63 ;i >= 0 ;i --)
        {
           LL ta = (L >> i) &1;
           LL tb = (R >> i) &1;
           if(ta == tb)
           {
              ans1 += ta << i ; 
              ans2 += ta << i ; 
           }else
           {
               break;
           }
        }
        for(LL j = i ;j >= 0;j --)
        {
            ans1 += 1ll << j ;     
        }
        printf("Case %d: %lld %lld
",CA,ans1,ans2);
     }
return 0;
}