2025-08-22 15:53:34 +0000 UTC

class Solution:
    def countPrefixSuffixPairs(self, words: List[str]) -> int:
        res = 0
        for i in range(len(words)):
            w1 = words[i]
            for j in range(i + 1, len(words)):
                w2 = words[j]
                if w2.startswith(w1) and w2.endswith(w1):
                    res += 1
        return res