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 PyPy3 (2.4.0) (judge verdict: Runtime Error)

import copy
from collections import deque
sima = [list(input()) for i in range(10)]
riku = 0
ikisaki = [(1,0),(-1,0),(0,1),(0,-1)]

for i in range(10):
    for j in range(10):
        if sima[i][j] == "o":
            riku += 1

for i in range(10):
    for j in range(10):
        if sima[i][j] == "o":
            continue
        cou = 0
        karisima = copy.deepcopy(sima)
        karisima[i][j] = "o"
        d = deque()
        d.append((i,j))
        tansaku = [[True for p in range(10)] for q in range(10)]
        while d:
            y , x = d.popleft()
            tansaku[y][x] = False
            cou += 1
            for ney , nex in ikisaki:
                if 0 <= x + nex <= 9 and 0 <= y + ney <= 9:
                    if tansaku[y+ney][x+nex] and karisima[y+ney][x+nex] == "o":
                        d.append((y+ney,x+nex))
        if cou == riku + 1:
            print("YES")
            exit()
print("NO")