#include <iostream>
using namespace std;

long long compute_xor(long long n) {
    int mod = n % 4;
    if (mod == 0) return n;
    else if (mod == 1) return 1;
    else if (mod == 2) return n + 1;
    else return 0;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int T;
    cin >> T;
    while (T--) {
        long long l, r;
        cin >> l >> r;
        long long result = compute_xor(r) ^ compute_xor(l - 1);
        cout << result << '\n';
    }
    
    return 0;
}

#include<bits/stdc++.h>
#define int long long
using namespace std;
int t,l,r,cm[65];
int cg(int x)
{
    int ans=0;
    for(int i=1;x>=cm[i-1];i++)
    {
        int a1=x/cm[i],a2=x%cm[i],dans=0;
        if(i==1)dans=a1%2^(a2==1);
        else if(a2>=cm[i-1]&&a2%2==0)dans^=cm[i-1];
        ans^=dans;
    }
    return ans;
}
signed main()
{
    scanf("%lld",&t);
    cm[0]=1;
    for(int i=1;i<=63;i++)
        cm[i]=cm[i-1]*2;
    while(t--)
    {
        scanf("%lld%lld",&l,&r);
        printf("%lld\n",cg(l-1)^cg(r));
    }
    return 0;
}