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').

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.

Constraints

• $1 \leq |s| \leq 10^5$
• $1 \leq |t| \leq 10^5$
• s and t consists of lowercase English letters.

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.

见题面 Input 部分

见题面 Output 部分