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 Java7 (OpenJDK 1.7.0) (judge verdict: Runtime Error)

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        String[] alphabet = new String[26];
        char c = 'a';
        for (int i = 0; i < 26; i++){
            alphabet[i] = String.valueOf(c++);
        }

        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        sc.nextLine();
        String t = sc.nextLine();
        Map<String, Integer> m = new HashMap<>();
        Map<String, Integer> tmp = new HashMap<>();
        String[] str  = t.split("");
        String[] S = s.split("");
        for(String string:str){
            int v;
            if(m.containsKey(string)){
                v=m.get(string) + 1;
            }else {
                v = 1;
            }
            m.put(string,v);
            tmp.put(string,v);
        }

        for(String j:S){
            if (m.containsKey(j)){
                int k = m.get(j);
                if (k>0){
                    m.put(j,k-1);
                }
            }else {
                System.out.println(-1);
                break;
            }
        }

        double tmp2=1;
        String min = "";
        for (String j:alphabet){
            if (tmp.containsKey(j)){
                double i = (tmp.get(j)-m.get(j))/tmp.get(j);
                if (tmp2>i){
                    tmp2=i;
                    min = j;
                }
            }
        }

        int count = (int)Math.floor(1.0/tmp2) + 1;
        int r = tmp.get(min)-(m.get(min)*count);
        int count2=0;
        for(String j:S){
           if (j.equals(min)){
               r--;
           }
            if(r==0){
                break;
            }
            count2++;
        }
        System.out.println(S.length*count + count2);



    }
}