Package g2901_3000.s2973_find_number_of_coins_to_place_in_tree_nodes

Class Solution

java.lang.Object
g2901_3000.s2973_find_number_of_coins_to_place_in_tree_nodes.Solution
public class Solution extends java.lang.Object
2973 - Find Number of Coins to Place in Tree Nodes.

Hard

You are given an undirected tree with n nodes labeled from 0 to n - 1, and rooted at node 0. You are given a 2D integer array edges of length n - 1, where edges[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the tree.

You are also given a 0-indexed integer array cost of length n, where cost[i] is the cost assigned to the ith node.

You need to place some coins on every node of the tree. The number of coins to be placed at node i can be calculated as:

  • If size of the subtree of node i is less than 3, place 1 coin.
  • Otherwise, place an amount of coins equal to the maximum product of cost values assigned to 3 distinct nodes in the subtree of node i. If this product is negative , place 0 coins.

Return an array coin of size n such that coin[i] is the number of coins placed at node i.

Example 1:

Input: edges = [[0,1],[0,2],[0,3],[0,4],[0,5]], cost = [1,2,3,4,5,6]

Output: [120,1,1,1,1,1]

Explanation: For node 0 place 6 * 5 * 4 = 120 coins. All other nodes are leaves with subtree of size 1, place 1 coin on each of them.

Example 2:

Input: edges = [[0,1],[0,2],[1,3],[1,4],[1,5],[2,6],[2,7],[2,8]], cost = [1,4,2,3,5,7,8,-4,2]

Output: [280,140,32,1,1,1,1,1,1]

Explanation: The coins placed on each node are: - Place 8 * 7 * 5 = 280 coins on node 0. - Place 7 * 5 * 4 = 140 coins on node 1. - Place 8 * 2 * 2 = 32 coins on node 2. - All other nodes are leaves with subtree of size 1, place 1 coin on each of them.

Example 3:

Input: edges = [[0,1],[0,2]], cost = [1,2,-2]

Output: [0,1,1]

Explanation: Node 1 and 2 are leaves with subtree of size 1, place 1 coin on each of them. For node 0 the only possible product of cost is 2 * 1 * -2 = -4. Hence place 0 coins on node 0.

Constraints:

  • 2 <= n <= 2 * 104
  • edges.length == n - 1
  • edges[i].length == 2
  • 0 <= ai, bi < n
  • cost.length == n
  • 1 <= |cost[i]| <= 104
  • The input is generated such that edges represents a valid tree.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    long[]
    placedCoins(int[][] edges, int[] cost)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • placedCoins

      public long[] placedCoins(int[][] edges, int[] cost)