func_code_string: #include <bits/stdc++.h>   using namespace std;   const int M = 10;   set<int> s[M];   int n, p[M];   bool check(int x) {     vector<int> b;     while (x) {       b.push_back(x % 10);       x /= 10;     }     if (b.size() > n) return false;     for (int i = 0; i < b.size(); i++)       if (s[p[i]].find(b[i]) == s[p[i]].end()) return false;     return true;   }   int main() {     cin >> n;     for (int i = 0; i < n; i++) {       p[i] = i;       for (int j = 0; j < 6; j++) {         int x;         cin >> x;         s[i].insert(x);       }     }     for (int x = 1;; x++) {       int fnd = false;       for (int i = 0; i < n; i++) p[i] = i;       do {         if (check(x)) fnd = true;       } while (next_permutation(p, p + n));       if (!fnd) return cout << x - 1 << endl, 0;     }     return 0;   }   