Problem Description Bit operation is a common computing method in computer science ,Now we have two positive integers A and B ,Please find a positive integer C that minimize the value of the formula (A  xor  C)  &  (B  xor  C) .Sometimes we can find a lot of C to do this ,So you need to find the smallest C that meets the criteria .

For example ,Let's say A is equal to 5 and B is equal to 3 ,we can choose C=1,3.... ,so the answer we're looking for C is equal to 1.

If the value of the expression is 0 when C=0, please print 1.
 

 

Input The input file contains T test samples.(1<=T<=100)

The first line of input file is an integer T.

Then the T lines contains 2 positive integers, A and B, (1≤A,B<232)  

 

Output For each test case,you should output the answer and a line for each answer.  

 

Sample Input 1 3 5  

 

Sample Output 1  

#include <bits/stdc++.h>

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>
#include <cstring>
#include <cstdlib>
#include <map>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <cmath>
typedef long long ll;
using namespace std;
const int INT=1e6+5;
#define lson rt<<1, l, m  
#define rson rt<<1|1, m+1, r
#define read(x) scanf("%d",&x)
#define lread(x) scanf("%lld",&x);
#define pt(x) printf("%d\n",(x))
#define cn cin>>
#define ct cout<<
#define en <<endl
#define rep(j, k) for (int i = (int)(j); i <= (int)(k); i++)
#define mem(s,t) memset(s,t,sizeof(s))
#define re return 0;


typedef long long ll;

int main()
{
    ll t,n,m,k;
    cn t ;
    while(t--)
    {
        cn n>>m;
        if(n&m) ct (n&m) en;
        else ct 1 en ;

    }
    re 
}