#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;
#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()
using ll = long long;
constexpr int INF = 0x3f3f3f3f;
constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr double EPS = 1e-8;
constexpr int MOD = 1000000007;
// constexpr int MOD = 998244353;
constexpr int DY4[]{1, 0, -1, 0}, DX4[]{0, -1, 0, 1};
constexpr int DY8[]{1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DX8[]{0, -1, -1, -1, 0, 1, 1, 1};
template <typename T, typename U>
inline bool chmax(T& a, U b) { return a < b ? (a = b, true) : false; }
template <typename T, typename U>
inline bool chmin(T& a, U b) { return a > b ? (a = b, true) : false; }
struct IOSetup {
  IOSetup() {
    std::cin.tie(nullptr);
    std::ios_base::sync_with_stdio(false);
    std::cout << fixed << setprecision(20);
  }
} iosetup;

void solve() {
  ll l, r; cin >> l >> r;
  if ((r - l) % 8 == 0) {
    cout << l + r << '\n';
  } else if ((r - l) % 8 < 4) {
    cout << 1 << '\n';
  } else if ((r - l) % 8 == 4) {
    cout << l + r + 1 << '\n';
  } else {
    cout << 0 << '\n';
  }
}

int main() {
  int t; cin >> t;
  while (t--) solve();
  return 0;

  constexpr int M = 30;
  REP(l, M) FOR(r, l, M) {
    int x = 0;
    FOR(i, l, r + 1) for (int j = i; j <= r && i + j <= l + r; ++j) x ^= i + j;
    cout << x << " \n"[r + 1 == M];
  }
}