func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m, num, maxs = INT_MIN, mins = INT_MAX, mins2 = INT_MAX;     cin >> n >> m;     vector<int> v1;     vector<int> v2;     for (int i = 0; i < n; i++) {       cin >> num;       v1.push_back(num);       maxs = max(maxs, num);       mins2 = min(mins2, num);     }     for (int i = 0; i < m; i++) {       cin >> num;       v2.push_back(num);       if (num <= maxs) {         cout <<  -1 ;         return 0;       }       mins = min(mins, num);     }     for (int i = 0; i < n; i++) {       if (2 * v1[i] <= maxs) {         cout << maxs;         return 0;       }     }     for (int i = 0; i < n; i++) {       if (2 * mins2 <= mins - 1) {         cout << 2 * mins2;         return 0;       }       if (2 * v1[i] <= mins - 1) {         cout << mins - 1;         return 0;       }     }     cout <<  -1 ;     return 0;   }   