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) {
        // write code here
        int n = str1.length(), m = str2.length();
        vector<int> prev(m + 1), cur(m + 1);
        for (int j = 0; j <= m; j++) prev[j] = j;
        for (int i = 1; i <= n; i++) {
            cur[0] = i;
            for (int j = 1; j <= m ; j++) {
                int cost = str1[i - 1] == str2[j - 1] ? 0 : 1;
                cur[j] = min({prev[j - 1] + cost, prev[j] + 1, cur[j -1] + 1});
            }
            swap(prev, cur);
        }
        return prev[m];
    }
};