#include using namespace std; using ll = long long; #define rep(i, n) for (int i = 0; i < n; i++) #define all(v) v.begin(), v.end() template inline bool chmax(T& a, U b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, U b) { if (a > b) { a = b; return true; } return false; } constexpr int INF = 1000000000; constexpr ll llINF = 3000000000000000000; constexpr int mod = 998244353; const ll half = (mod + 1) / 2; constexpr double eps = 1e-10; vector prime_list(int n) { vector v(n + 1), res; for (int i = n; i >= 2; i--) { for (int j = i; j <= n; j += i) v[j] = i; } for (int i = 2; i <= n; i++) { if (v[i] == i) res.push_back(i); } return res; } vector next_divisor(int n) { vector v(n + 1); for (int i = n; i >= 2; i--) { for (int j = i; j <= n; j += i) v[j] = i; } return v; } ll modpow(ll a, ll b, ll m = mod) { ll res = 1; while (b) { if (b & 1) { res *= a; res %= m; } a *= a; a %= m; b >>= 1; } return res; } vector inv, fact, factinv; void init_fact(int n) { inv.resize(n + 1); fact.resize(n + 1); factinv.resize(n + 1); inv[0] = 0; inv[1] = 1; fact[0] = 1; factinv[0] = 1; for (ll i = 1; i <= n; i++) { if (i >= 2) inv[i] = mod - ((mod / i) * inv[mod % i] % mod); fact[i] = (fact[i - 1] * i) % mod; factinv[i] = factinv[i - 1] * inv[i] % mod; } } ll modinv(ll a, ll m = mod) { // gcd(a,m) must be 1 ll b = m, u = 1, v = 0; while (b) { ll t = a / b; a -= t * b; swap(a, b); u -= t * v; swap(u, v); } u %= m; if (u < 0) u += m; return u; } ll comb(int a, int b) { if (a < b) return 0; if (a < 0) return 0; return fact[a] * factinv[a - b] % mod * factinv[b] % mod; } ll f(ll a, ll b) { if (b < a) return 0; // cout << a << " " << b << endl; // a^a+4^a+8^a+12=0 while (b % 4 != a % 4) b--; ll res = 0; while (1) { if ((b / 4) % 4 == 3 || b <= 0) break; res ^= b; b -= 4; } return res; } void solve() { ll l, r; cin >> l >> r; ll a = l * 2, b = l + r; // ans=(a^a+1^a+4^a+5^...)*2 cout << (f(a % 4, b) ^ f(a % 4, a - 1) ^ f((a + 1) % 4, b) ^ f((a + 1) % 4, a - 1)) << endl; } int main() { cin.tie(0); ios::sync_with_stdio(false); int t; cin >> t; while (t--) solve(); }