#include<cstdio>
#include<cstring>
#include<cassert>
#include<vector>
#include<list>
#include<queue>
#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<cmath>
#include<cstdlib>
#include<ctime>
#include<fstream>
#include<typeinfo>
#include<locale>
#include<iterator>
#include<valarray>
#include<complex>
#include<climits>

using namespace std;

#define xx         first
#define yy         second
#define pb         push_back
#define mp         make_pair
#define LL         long long
#define inf        INT_MAX/3
#define mod        100000007ll
#define PI         acos(-1.0)
#define linf       (1ll<<60)-1
#define FOR(I,A,B) for(int I = (A); I < (B); ++I)
#define REP(I,N)   FOR(I,0,N)
#define ALL(A)     ((A).begin(), (A).end())
#define set0(ar)   memset(ar,0,sizeof ar)
#define vsort(v)   sort(v.begin(),v.end())
#define setinf(ar) memset(ar,126,sizeof ar)

//cout << fixed << setprecision(20) << p << endl;

template <class T> inline T bigmod(T p,T e,T M){
    LL ret = 1;
    for(; e > 0; e >>= 1){
        if(e & 1) ret = (ret * p) % M;
        p = (p * p) % M;
    } return (T)ret;
}
template <class T> inline T gcd(T a,T b){if(b==0)return a;return gcd(b,a%b);}
template <class T> inline T modinverse(T a,T M){return bigmod(a,M-2,M);}

vector < pair < int, pair < int, int > > > vc[2][2][2][2];

LL dp[70][2][2][2][2], ar[70][2], br[70][2];
LL go(int c, int f1, int f2, int g1, int g2){
    if(c < 0) return 0;
    LL &ret = dp[c][f1][f2][g1][g2];
    if(ret != -1) return ret;
    ret = 0;

    REP(i, vc[f1][f2][ar[c][0]][ar[c][1]].size()){
        REP(j, vc[g1][g2][br[c][0]][br[c][1]].size()){
            LL v = 0;
            if(vc[f1][f2][ar[c][0]][ar[c][1]][i].xx ^ vc[g1][g2][br[c][0]][br[c][1]][j].xx) v = 1ll<<c;
            ret = max(ret, v + go(c - 1, vc[f1][f2][ar[c][0]][ar[c][1]][i].yy.xx, vc[f1][f2][ar[c][0]][ar[c][1]][i].yy.yy
                                  , vc[g1][g2][br[c][0]][br[c][1]][j].yy.xx, vc[g1][g2][br[c][0]][br[c][1]][j].yy.yy));
        }
    }

    return ret;
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    REP(i, 2){
        REP(j, 2){
            REP(k, 2){
                REP(l, 2){
                    REP(p, 2){
                        if(i == 0 && p > k) continue;
                        if(j == 0 && p < l) continue;
                        if(i == 0 && p == k){
                            if(j == 0 && p == l) vc[i][j][k][l].pb(mp(p, mp(i, j)));
                            else vc[i][j][k][l].pb(mp(p, mp(i, 1)));
                        } else {
                            if(j == 0 && p == l) vc[i][j][k][l].pb(mp(p, mp(1, j)));
                            else vc[i][j][k][l].pb(mp(p, mp(1, 1)));
                        }
                    }
                }
            }
        }
    }

    int T; cin >> T;
    while(T--){
        LL a, b, c, d; cin >> a >> b >> c >> d;
        REP(i, 60){
            ar[i][0] = (b & (1ll<<i)) > 0 ? 1 : 0;
            ar[i][1] = (a & (1ll<<i)) > 0 ? 1 : 0;
            br[i][0] = (d & (1ll<<i)) > 0 ? 1 : 0;
            br[i][1] = (c & (1ll<<i)) > 0 ? 1 : 0;
        }

        memset(dp, -1, sizeof dp);

        cout << go(60, 0, 0, 0, 0) << endl;
    }
}