leetcode专题训练 72. Edit Distance

很简单的dp。

class Solution {
public:
    int minDistance(string word1, string word2) {
        string s1 = word1;
        string s2 = word2;
        int l1 = s1.length();
        int l2 = s2.length();
        if(l1 == 0) {
            return l2;
        } else if(l2 == 0) {
            return l1;
        }
        int dp[l1+1][l2+1];
        memset(dp, 0, sizeof(dp));
        for(int i = 0; i <= l1; i++) {
            dp[i][0] = i;
        }
        for(int i = 0; i <= l2; i++) {
            dp[0][i] = i;
        }
        for(int i = 1; i <= l1; i++) {
            for(int j = 1; j <= l2; j++) {
                if(s1[i-1] == s2[j-1]) {
                    dp[i][j] = min(dp[i-1][j]+1, dp[i][j-1]+1);
                    dp[i][j] = min(dp[i][j], dp[i-1][j-1]);
                } else {
                    dp[i][j] = min(dp[i-1][j]+1, dp[i][j-1]+1);
                    dp[i][j] = min(dp[i][j], dp[i-1][j-1]+1);
                }
            }
        }
        return dp[l1][l2];
    }
};