题解 | 编辑距离(一)

class Solution {
public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param str1 string字符串 
     * @param str2 string字符串 
     * @return int整型
     */
    int editDistance(string str1, string str2) {
        int m = str1.size(), n = str2.size();
        str1 = ' ' + str1, str2 = ' ' + str2;
        vector<vector<int>> f(m + 1, vector<int> (n + 1));
        for (int i = 0; i <= m; i++) f[i][0] = i;
        for (int j = 1; j <= n; j++) f[0][j] = j;
        for (int i = 1; i <= m; i++) {
            for (int j = 1; j <= n; j++) {
                f[i][j] = min(f[i][j - 1], f[i - 1][j]) + 1;
                int t = str1[i] != str2[j];
                f[i][j] = min(f[i][j], f[i - 1][j - 1] + t);
            }
        }
        return f[m][n];
    }
};