#include <bits/stdc++.h>
using namespace std;
#define rep(i, l, r) for (ll i = (l); i < (r); ++i)
using ll = long long;

int main(){
    random_device rnd;
    mt19937_64 mt(rnd());
    ll t;
    cin>>t;
    rep(i,0,t){
        ll n,m;
        cin>>n>>m;
        ll a=m;
        ll b=n+m-1;
        ll ans=0;
        rep(i,0,32){
            if(b-a>=((ll)1<<i)){
                ans+=(((b+((ll)1<<(i)))/((ll)1<<(i+1)))-((a+((ll)1<<(i)))/((ll)1<<(i+1))))*((ll)1<<i);
            }else{
                if((a&((ll)1<<i))==(b&((ll)1<<i)))break;
                ll d=0;
                for(ll j=35;j>=0;j--){
                    if(d==0){
                        if((!(a&((ll)1<<j)))&&((b&((ll)1<<j)))){
                            d=1;
                            ans+=((ll)1<<j);
                        }
                        continue;
                    }
                    if((a&((ll)1<<j))&&(!(b&((ll)1<<j))))ans+=((ll)1<<j);
                    else if((!(a&((ll)1<<j)))&&((b&((ll)1<<j))))break;
                }
                break;
            }
        }
        cout<<ans<<endl;
    }
}