Infinite Replacement

题意翻译

给一个只含小写字母 `a` 的字符串 $s$ 和一个用来替换的字符串 $t$ 。 你可以将 $s$ 中任意**一个**字母 `a` 用 $t$ 来替换，替换的次数不限。 对于每一个 $s$ 和 $t$ ，你可以得到几个不同的字符串？如果有无限个，输出 `-1` 。

题目描述

You are given a string $ s $ , consisting only of Latin letters 'a', and a string $ t $ , consisting of lowercase Latin letters. In one move, you can replace any letter 'a' in the string $ s $ with a string $ t $ . Note that after the replacement string $ s $ might contain letters other than 'a'. You can perform an arbitrary number of moves (including zero). How many different strings can you obtain? Print the number, or report that it is infinitely large. Two strings are considered different if they have different length, or they differ at some index.

输入输出格式

输入格式

The first line contains a single integer $ q $ ( $ 1 \le q \le 10^4 $ ) — the number of testcases. The first line of each testcase contains a non-empty string $ s $ , consisting only of Latin letters 'a'. The length of $ s $ doesn't exceed $ 50 $ . The second line contains a non-empty string $ t $ , consisting of lowercase Latin letters. The length of $ t $ doesn't exceed $ 50 $ .

输出格式

For each testcase, print the number of different strings $ s $ that can be obtained after an arbitrary amount of moves (including zero). If the number is infinitely large, print -1. Otherwise, print the number.

输入输出样例

输入样例 #1

3
aaaa
a
aa
abc
a
b

输出样例 #1

1
-1
2

说明

In the first example, you can replace any letter 'a' with the string "a", but that won't change the string. So no matter how many moves you make, you can't obtain a string other than the initial one. In the second example, you can replace the second letter 'a' with "abc". String $ s $ becomes equal to "aabc". Then the second letter 'a' again. String $ s $ becomes equal to "aabcbc". And so on, generating infinitely many different strings. In the third example, you can either leave string $ s $ as is, performing zero moves, or replace the only 'a' with "b". String $ s $ becomes equal to "b", so you can't perform more moves on it.