Leetcode 3276. Select Cells in Grid With Maximum Score

• Leetcode 3276. Select Cells in Grid With Maximum Score
  • 1. 解题思路
  • 2. 代码实现

• 题目链接：3276. Select Cells in Grid With Maximum Score

1. 解题思路

这一题思路上的话就是一个动态规划，我们从大到小将所有元素进行一下排序，然后依次考察一下各个元素是否可以取即可。

2. 代码实现

给出python代码实现如下：

class Solution:
    def maxScore(self, grid: List[List[int]]) -> int:
        n, m = len(grid), len(grid[0])
        elems = [(grid[i][j], i, j) for i in range(n) for j in range(m)]
        elems = sorted(elems, reverse=True)
        if n == 1:
            return elems[0][0]
        N = len(elems)
        
        @lru_cache(None)
        def dp(idx, status):
            if idx >= N or status == 1023:
                return 0
            x, i, j = elems[idx]
            if status & (1 << i) > 0:
                return dp(idx+1, status)
            nxt = idx+1
            while nxt < N and elems[nxt][0] == x:
                nxt += 1
            return max(x + dp(nxt, status | (1<<i)), dp(idx+1, status))
        
        return dp(0, 0)

提交代码评测得到：耗时555ms，占用内存121.9MB。