#include <bits/stdc++.h>   using namespace std;   int a, b, c, d, e;   int ar[200100];   int ar1[200100];   int main() {     vector<int> arr(200100);     string s, s1;     cin >> s;     cin >> s1;     a = min(s.length(), s1.length());     b = a;     c = 1;     while ((c <= a) && (s[s.length() - c] == s1[s1.length() - c])) ++c;     cout << (a - c + 1) + max(s.length(), s1.length()) - c + 1;   }   