#include <bits/stdc++.h>

using namespace std;
using ll = long long;

void solve(){
    ll L, R, ans=0;
    cin >> L >> R;

    if (((R-L+1)/4) % 2 == 1) ans = 1;
    for (ll i=L*2+(R-L+1)/4*4; i<=L+R; i++){
        if (((i-L*2)/2+1) % 2 == 1) ans ^= i;
    }
    cout << ans << endl;
}

int main(){

    int T;
    cin >> T;
    while(T){
        T--;
        solve();
    }

    return 0;
}