Package g2901_3000.s2973_find_number_of_coins_to_place_in_tree_nodes

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    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 <code>edgesi = a<sub>i</sub>, b<sub>i</sub></code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> 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 <code>i<sup>th</sup></code> 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:

    • <code>2 <= n <= 2 * 10<sup>4</sup></code>

    • edges.length == n - 1

    • edges[i].length == 2

    • <code>0 <= a<sub>i</sub>, b<sub>i</sub>< n</code>

    • cost.length == n

    • <code>1 <= |costi| <= 10<sup>4</sup></code>

    • The input is generated such that edges represents a valid tree.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final LongArray placedCoins(Array<IntArray> edges, IntArray cost)

      • Methods inherited from class java.lang.Object

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