秋叶集

 

 

 1 class Solution {
 2 public:
 3     int minimumOperations(string leaves) {
 4         int n = leaves.size();
 5         vector<vector<int>> f(n, vector<int>(3));
 6         f[0][0] = (leaves[0] == 'y');
 7         f[0][1] = f[0][2] = f[1][2] = INT_MAX;
 8         for (int i = 1; i < n; ++i) {
 9             int isRed = (leaves[i] == 'r');
10             int isYellow = (leaves[i] == 'y');
11             f[i][0] = f[i - 1][0] + isYellow;
12             f[i][1] = min(f[i - 1][0], f[i - 1][1]) + isRed;
13             if (i >= 2) {
14                 f[i][2] = min(f[i - 1][1], f[i - 1][2]) + isYellow;
15             }
16         }
17         return f[n - 1][2];
18     }
19 };

看懂了 简单

posted @ 2020-10-03 00:51  然终酒肆  阅读(158)  评论(0)  编辑  收藏  举报