Uniform Suffix Subset

You are given T test cases. In each test case, you are provided with an integer N denoting the number of words and an integer K denoting the length of the suffix to consider. Then, N words are given.

Your task is to determine whether it is possible to choose a subset of at least two words such that all the words in the subset share the same last K characters. In other words, check if there exists a suffix of length K that appears in at least two words.

If such a suffix exists, output YES; otherwise, output NO.

Note: If a word has length less than K, treat the entire word as its suffix.

inputFormat

The input is given through standard input (stdin) and follows the format below:

• The first line contains an integer T (1 ≤ T ≤ 100) denoting the number of test cases.
• For each test case:
  • The first line contains two integers N and K (1 ≤ N ≤ 100, 1 ≤ K ≤ 100), where N is the number of words and K is the length of the suffix to consider.
  • The second line contains N space-separated words. Each word consists of lowercase English letters.

outputFormat

For each test case, print a single line containing either YES if there exists at least one suffix (of length K) that appears in at least two words, or NO if no such suffix exists.

## sample

1
4 2
hello jello mellow yellow

YES

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