1class Solution {2    public int minDistance(String word1, String word2) {3        int m = word1.length(), n = word2.length();4        int[][] dp = new int[m + 1][n + 1];5        for (int i = 0; i <= m; i++) dp[i][0] = i;6        for (int j = 0; j <= n; j++) dp[0][j] = j;7        for (int i = 1; i <= m; i++) {8            for (int j = 1; j <= n; j++) {9                if (word1.charAt(i - 1) == word2.charAt(j - 1))10                    dp[i][j] = dp[i - 1][j - 1];11                else dp[i][j] = 1 + Math.min(dp[i - 1][j - 1],12                    Math.min(dp[i - 1][j], dp[i][j - 1]));13            }14        }15        return dp[m][n];16    }17}