Problem:
Score : 500 points

Problem Statement

Given are two strings s and t consisting of lowercase English letters. Determine if there exists an integer i satisfying the following condition, and find the minimum such i if it exists.

Let s' be the concatenation of 10^{100} copies of s. t is a subsequence of the string {s'}_1{s'}_2\ldots{s'}_i (the first i characters in s').

Notes

A subsequence of a string a is a string obtained by deleting zero or more characters from a and concatenating the remaining characters without changing the relative order. For example, the subsequences of contest include net, c, and contest.

Constraints

1 \leq |s| \leq 10^5

1 \leq |t| \leq 10^5

s and t consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

s
t

Output

If there exists an integer i satisfying the following condition, print the minimum such i; otherwise, print -1.

Sample Input 1

contest
son

Sample Output 1

10

t = son is a subsequence of the string contestcon (the first 10 characters in s' = contestcontestcontest...), so i = 10 satisfies the condition.

On the other hand, t is not a subsequence of the string contestco (the first 9 characters in s'), so i = 9 does not satisfy the condition.

Similarly, any integer less than 9 does not satisfy the condition, either. Thus, the minimum integer i satisfying the condition is 10.

Sample Input 2

contest
programming

Sample Output 2

-1

t = programming is not a substring of s' = contestcontestcontest.... Thus, there is no integer i satisfying the condition.

Sample Input 3

contest
sentence

Sample Output 3

33

Note that the answer may not fit into a 32-bit integer type, though we cannot put such a case here.

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <bits/stdc++.h>
#include <vector>
using namespace std;


 
int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
  
  
  string s,t;
  cin >> s >> t;
  
  
  /*or(int i=0;i<7;i++){
  	s+=s;
  }*/
  
  long long point=0;
  int i=0,j=0;
  
  //while(point<=10^100){
    
  	while(i<t.length()){
      if(j>=s.length()-1){
      	j=0;
        point++;
        if(point>=s.length()*10){
        point=-1;
          break;
        }
      }
    	if(t.at(i)==s.at(j)){
        	i++;
        	j++;
          if(i>=t.length()){
          	point=(point*s.length())+j;
            break;
          }
        }else{
        	j++;
        }
    }
  //}
  
  
  
  
  
  cout << point << endl;

}