Shortest Uncommon Subsequence
Easy Accuracy: 30.49% Submissions: 459 Points: 2

Given two strings S and T, find length of the shortest subsequence in S which is not a subsequence in T. If no such subsequence is possible, return -1. A subsequence is a sequence that appears in the same relative order, but not necessarily contiguous. A string of length n has 2^n different possible subsequences.

 

Input:

The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. The first line of each test case contains integers M and N where M denotes the length of first string and N denotes the length of second string.

The second line of each test case contains the two string S and T. Both string are comprised only of lower case alphabets.


Output:

Output the length of the shortest uncommon subsequence for each test case in a new line. If no such sub sequence is possible print -1.


Constraints:

1<= T <=100

1<= N,M <=500


Example:

Input:

1

5 5

babab babba

Output:

3

to report an issue on this page.

Editorial

We strongly recommend solving this problem on your own before viewing its editorial. Do you still want to view the editorial?

Yes

All Submissions

My Submissions:

Login to access your submissions.