LeetCode | 72. Edit Distance

 

题目：

Given two words word1 and word2, find the minimum number of operations required to convert word1 to word2.

You have the following 3 operations permitted on a word:

Insert a characterDelete a characterReplace a character

Example 1:

Input: word1 = "horse", word2 = "ros" Output: 3 Explanation: horse -> rorse (replace 'h' with 'r') rorse -> rose (remove 'r') rose -> ros (remove 'e')

Example 2:

Input: word1 = "intention", word2 = "execution" Output: 5 Explanation: intention -> inention (remove 't') inention -> enention (replace 'i' with 'e') enention -> exention (replace 'n' with 'x') exention -> exection (replace 'n' with 'c') exection -> execution (insert 'u')

代码：

class Solution { public: int minDistance(string word1, string word2) { int l1 = word1.length(); int l2 = word2.length(); vector<vector<int>> dp(l1 + 1, vector<int>(l2 + 1, 0)); for (int i = 1; i <= l1; i++) dp[i][0] = i; for (int i = 1; i <= l2; i++) dp[0][i] = i; for (int i = 1; i <= l1; i++) { for (int j = 1; j <= l2; j++) { if (word1[i-1] == word2[j-1]) { dp[i][j] = dp[i - 1][j - 1]; } else { dp[i][j] = min(min(dp[i - 1][j], dp[i][j - 1]), dp[i-1][j-1]) + 1; } } } return dp[l1][l2]; } };