LeetCode 72. Edit Distance

[woodyiiiiiii]

class Solution {
    public int minDistance(String word1, String word2) {
        
        int n1 = word1.length(), n2 = word2.length();
        int[][] dp = new int[n1 + 1][n2 + 1];
        
        for (int i = 1; i <= n1; ++i) {
            dp[i][0] = i;
        }
        for (int j = 1; j <= n2; ++j) {
            dp[0][j] = j;
        }
        
        for (int i = 1; i <= n1; ++i) {
            for (int j = 1; j <= n2; ++j) {
                if (word1.charAt(i - 1) == word2.charAt(j - 1)) {
                    dp[i][j] = dp[i - 1][j - 1];
                } else {
                    dp[i][j] = Math.min(dp[i - 1][j], Math.min(dp[i][j - 1], dp[i - 1][j - 1])) + 1;
                }
            }
        }
        
        return dp[n1][n2];
        
    }
}