原题链接:Leetcode 72. 编辑距离
class Solution {
public:
int minDistance(string word1, string word2) {
int m = word1.size();
int n = word2.size();
// dp[i][j]为把word1的前i个字符转换为word2的前j个字符所花的最少操作数
vector<vector<int