265A - Colorful Stones (Simplified Edition).

#include<bits/stdc++.h>

using namespace std;

int main()

{

    string s1,s2;

    cin>>s1>>s2;

    int j=0,pos=1;

    for(int i=0;i<s2.size();i++)

    {

       if(s1[j]==s2[i])

       {

           pos++;

           j++;

       }

    }

  cout<<pos<<endl;

}