func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize( Ofast )   using namespace std;   constexpr int LG = 60;   int N;   long long int ai, bi, bs;   long long int x[LG + 1];   inline bool ins(long long int v) {     for (int i = LG; i >= 0; --i) {       if (!((v >> i) & 1)) continue;       if (x[i]) {         v ^= x[i];       } else {         for (int j = i - 1; j >= 0; --j)           if ((v >> j) & 1) v ^= x[j];         for (int j = i + 1; j <= LG; ++j)           if ((x[j] >> i) & 1) x[j] ^= v;         x[i] = v;         return true;       }     }     return false;   }   int main() {     ios::sync_with_stdio(false);     cin.tie(NULL);     cin >> N;     int s = 0;     for (int i = 0; i < N; ++i) {       cin >> ai >> bi;       bs ^= bi, ai ^= bi;       if (ins(ai)) ++s;     }     for (int i = LG; i >= 0; --i)       if ((bs >> i) & 1) bs ^= x[i];     if (bs)       cout <<  1/1 n ;     else       cout << (1ll << s) - 1 <<  /  << (1ll << s) <<   n ;     return 0;   }   