func_code_string: #include <bits/stdc++.h>   using namespace std;   long long arr[101], N, T;   void Input() {     cin >> N;     memset(arr, 0, sizeof arr);     for (int i = 0; i < N; i++) {       long long tmp;       cin >> tmp;       arr[tmp]++;     }   }   void Solve() {     int one = 0, two = 0;     for (int i = 0; i <= 100; i++) {       if (arr[i] >= 2 && one == two) {         one++;         two++;       } else if (arr[i] >= 1) {         one++;       } else {         break;       }     }     cout << one + two <<   n ;   }   int main() {     cin >> T;     for (int i = 0; i < T; i++) {       Input();       Solve();     }   }   