func_code_string: #include <bits/stdc++.h>   using namespace std;   int r[8192];   vector<int> g[8192];   int ans[8192] = {       0,   };   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     int n;     cin >> n;     ans[0] = 1;     for (int i = 0; i < 8192; i++) {       g[i].push_back(0);     }     for (int i = 0; i < 8192; i++) {       r[i] = 8192;     }     for (int i = 0; i < n; i++) {       int x;       cin >> x;       for (const auto& key : g[x]) {         int to = (key ^ x);         ans[to] = 1;         while (r[to] > x) {           r[to]--;           if (r[to] != x) g[r[to]].push_back(to);         }       }       g[x].clear();     }     int cnt = 0;     for (int i = 0; i < 8192; i++) {       cnt += ans[i];     }     cout << cnt <<   n ;     for (int i = 0; i < 8192; i++) {       if (ans[i]) cout << i <<    ;     }     cout <<   n ;   }   