class Solution(object):def minDistance(self, word1, word2):""":type word1: str:type word2: str:rtype: int"""dp = [[0]*(len(word2)+1) for _ in range(len(word1)+1)]# 边界条件:当输入是一个空串和一个非空串时# 编辑距离为非空串的长度(插入i次或者删除i次)for i in range(len(word1)+1):dp[i][0] = ifor j in range(len(word2)+1):dp[0][j] = jfor i in range(1, len(word1)+1):for j in range(1, len(word2)+1):if word1[i-1] == word2[j-1]:# 两字符相同则无需操作dp[i][j] = dp[i-1][j-1]else:# 插入、删除、替换三者选一dp[i][j] = min(dp[i-1][j] + 1,dp[i-1][j-1] + 1,dp[i][j-1] + 1)return dp[len(word1)][len(word2)]s = Solution()
minEdit = s.minDistance('intention', 'execution')
print(minEdit)