文章目录

• [6031. 找出数组中的所有 K 近邻下标](https://leetcode-cn.com/problems/find-all-k-distant-indices-in-an-array/)
• [5203. 统计可以提取的工件](https://leetcode-cn.com/problems/count-artifacts-that-can-be-extracted/)
• [5227. K 次操作后最大化顶端元素](https://leetcode-cn.com/problems/maximize-the-topmost-element-after-k-moves/)
• [6032. 得到要求路径的最小带权子图](https://leetcode-cn.com/problems/minimum-weighted-subgraph-with-the-required-paths/)
• 总结

6031. 找出数组中的所有 K 近邻下标

看数据范围1 <= nums.length <= 1000，直接暴力2行搞定

class Solution:    def findKDistantIndices(self, nums: List[int], key: int, k: int) -> List[int]: keys = [i for i,v in enumerate(nums) if v == key] return sorted({j  for i in keys for j in range(len(nums)) if abs(i - j) <= k})

5203. 统计可以提取的工件

看数据范围1 <= n <= 1000，每个工件最多只覆盖4个单元格，直接哈希+暴力，2行搞定

class Solution:    def digArtifacts(self, n: int, artifacts: List[List[int]], dig: List[List[int]]) -> int: map = set([(a, b) for a, b in dig]) return sum(all((i, j) in map for i in range(r1, r2+1) for j in range(c1, c2+1)) for r1, c1, r2, c2 in artifacts)

5227. K 次操作后最大化顶端元素

这题比较吃细节，推荐大家看一下灵茶山艾府大佬的题解，1行就搞定了

class Solution:    def maximumTop(self, nums: List[int], k: int) -> int: return max(num for i, num in enumerate(nums) if i < k - 1 or i == k) if len(nums) > 1 or k % 2 == 0 else -1

6032. 得到要求路径的最小带权子图

三次dijkstra，可可也是看了题解之后才做出来，15行解法👇

class Solution:    def minimumWeight(self, n: int, edges: List[List[int]], src1: int, src2: int, dest: int) -> int: g1,g2=defaultdict(lambda:defaultdict(lambda:inf)),defaultdict(lambda:defaultdict(lambda:inf)) for u,v,w in edges:     g1[u][v],g2[v][u]=min(g1[u][v],w),min(g2[v][u],w)  def dijkstra(graph,s):     dist=[inf]*n;dist[s]=0     heap=[];heappush(heap,(0,s))     while heap:  d,u=heappop(heap)  for v in graph[u]:      if graph[u][v]+d<dist[v]:   dist[v]=graph[u][v]+d   heappush(heap,(dist[v],v))     return dist  a,b,c=dijkstra(g1,src1),dijkstra(g1,src2),dijkstra(g2,dest) return res if (res:=min(a[i]+b[i]+c[i] for i in range(n)))<inf else -1

总结

T4罚坐一小时/(ㄒoㄒ)/~~，T1+T2+T3+T4共2+2+1+15=20行代码，勉强完成【20行完成周赛】的目标！