CF1295C.Obtain The String
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题目描述
You are given two strings s and t consisting of lowercase Latin letters. Also you have a string z which is initially empty. You want string z to be equal to string t . You can perform the following operation to achieve this: append any subsequence of s at the end of string z . A subsequence is a sequence that can be derived from the given sequence by deleting zero or more elements without changing the order of the remaining elements. For example, if z=ac , s=abcde , you may turn z into following strings in one operation:
- z=acace (if we choose subsequence ace );
- z=acbcd (if we choose subsequence bcd );
- z=acbce (if we choose subsequence bce ).
Note that after this operation string s doesn't change.
Calculate the minimum number of such operations to turn string z into string t .
输入格式
The first line contains the integer T ( 1≤T≤100 ) — the number of test cases.
The first line of each testcase contains one string s ( 1≤∣s∣≤105 ) consisting of lowercase Latin letters.
The second line of each testcase contains one string t ( 1≤∣t∣≤105 ) consisting of lowercase Latin letters.
It is guaranteed that the total length of all strings s and t in the input does not exceed 2⋅105 .
输出格式
For each testcase, print one integer — the minimum number of operations to turn string z into string t . If it's impossible print −1 .
输入输出样例
输入#1
3 aabce ace abacaba aax ty yyt
输出#1
1 -1 3