本文共 548 字，大约阅读时间需要 1 分钟。

class Solution:    def minDistance(self, word1: str, word2: str) -> int:        dp = [[0]*(len(word2)+1) for _ in range(len(word1)+1)]        for i in range(len(dp)):            dp[i][0] = i        for j in range(len(dp[0])):            dp[0][j] = j                for i in range(1, len(word1)+1):            for j in range(1, len(word2)+1):                if word1[i-1] == word2[j-1]:                    dp[i][j] = dp[i-1][j-1]                else:                    dp[i][j] = min(dp[i][j-1],dp[i-1][j],dp[i-1][j-1]) + 1        return dp[-1][-1]