#include <bits/stdc++.h>   using namespace std;   int n, m;   int ans = 654;   vector<int> a, b, us(10);   int main() {     cin >> n >> m;     a.resize(n);     b.resize(m);     for (int i = 0; i < n; ++i) {       cin >> a[i];       us[a[i]] = 1;     }     for (int j = 0; j < m; ++j) {       cin >> b[j];       if (us[b[j]] == 1) {         ans = min(ans, b[j]);       }     }     sort(a.begin(), a.end());     sort(b.begin(), b.end());     cout << min({(a[0] * 10) + b[0], (b[0] * 10) + a[0], ans});   }   