QUESTION

You are given two string S and T. Find the maximal length of some prefix of the string S which occurs in strings T as subsequence.\n\nInput\nThe first line contains string S. The second line contains string T. Both strings consist of lowecase Latin letters.\n\nOutput\nOutput one integer – answer to the question.\n\nConstraints\n1 <= length of S, T <= 10^6.

ANSWER

#include<bits/stdc++.h>
using namespace std;
int main(){
 
		string s1,s2;
cin>>s1>>s2;
int count = 0 ;
int pos = -1;
int k = s2.length();
for(int i=0;i<s1.length();i++)
{
	
	pos = s2.find(s1[i],pos+1);
	if(pos!=string::npos)
		count ++;
	else
        break;
}
cout<<count;
 
 
}