func_code_string: #include <bits/stdc++.h>   using namespace std;   ifstream in( input.txt );   ofstream out( output.txt );   int main() {     vector<int> a;     int n, x;     cin >> n >> x;     a.resize(100001);     vector<int> b;     for (int i = 0; i < n; i++) {       int t;       cin >> t;       a[t]++;       b.push_back(t);     }     unsigned long long ans = 0;     for (int i = 0; i < n; i++) {       if ((b[i] ^ x) == b[i]) {         ans += (a[b[i]] - 1);       } else if ((b[i] ^ x) < 100001) {         ans += a[b[i] ^ x];       }       a[b[i]]--;     }     cout << ans;   }   