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>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0; i < (ll)(n); i++)
#define rep2(i, a, n) for(ll i = a; i < (ll)(n); i++)
#define memi cout << endl
#define kono(n) cout << fixed << setprecision(n)
#define all(c) (c).begin(), (c).end()
#define pb push_back
#define hina cout << ' '
#define in(n) cin >> n
#define in2(n, m) cin >> n >> m
#define in3(n, m, l) cin >> n >> m >> l
#define out(n) cout << n
const ll mei = (ll)1e9 + 7;

int main(){
  string s, t;
  in2(s, t);
  ll a, b;
  vector<ll> c(26, 0), d(26, 0);
  char f = 'a';
  rep(i, 26){
    rep(j, s.size()){
      if(s[j] == f)
        c[i]++;
    }
    f++;
  }
  f = 'a';
  rep(i, 26){
    rep(j, t.size()){
      if(t[j] == f)
        d[i]++;
    }
    f++;
  }
  a = 0;
  rep(i, 26){
    if(c[i] == 0 && d[i] != 0){
      out(-1);
      memi;
      return 0;
    }
    else if(c[i] == 0 && d[i] == 0)
      continue;
    else{
      a = max(a, d[i] / c[i]);
      d[i] %= c[i];
    }
  }
  a *= s.size();
  f = 'a';
  b = 0;
  rep(i, 26){
    rep(j, s.size()){
      if(s[j] == f){
        d[i]--;
        if(d[i] == 0)
          b = max(b, i + 1ll);
      }
    }
    f++;
  }
  out(a + b);
  memi;
}