#include <bits/stdc++.h>   using namespace std;   int main(int argc, char *argv[]) {     ios::sync_with_stdio(false);     cin.tie(nullptr);     string s, t;     cin >> s >> t;     int ns = s.size() - 1;     int nt = t.size() - 1;     bool stop = true;     while (stop && (ns >= 0 && nt >= 0)) {       if (s[ns] != t[nt]) {         stop = false;       }       if (stop) {         ns--;         nt--;       }     }     int r = ns + nt + 2;     cout << r;     return 0;   }   