Tree of Coprimes

There is a tree (i.e., a connected, undirected graph that has no cycles) consisting of n nodes numbered from 0 to n - 1 and exactly n - 1 edges. Each node has a value associated with it, and the root of the tree is node 0.

To represent this tree, you are given an integer array nums and a 2D array edges. Each nums[i] represents the i^th node's value, and each edges[j] = [uj, vj] represents an edge between nodes uj and vj in the tree.

Two values x and y are coprime if gcd(x, y) == 1, where gcd(x, y) is the greatest common divisor of x and y.

An ancestor of a node i is any other node on the shortest path from node i to the root. A node is not considered an ancestor of itself.

Return an array ans of size n, where ans[i] is the closest ancestor to node i such that nums[i] and nums[ans[i]] are coprime, or -1 if there is no such ancestor.

Example 1
Inputnums = [2,3,3,2], edges = [[0,1],[1,2],[1,3]]
Output[-1,0,0,1]
Node 0 has no coprime ancestor, node 1's closest coprime ancestor is 0, node 2 skips node 1 because their values are not coprime and uses 0, and node 3 uses node 1.
Example 2
Inputnums = [5,6,10,2,3,6,15], edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]
Output[-1,0,-1,0,0,0,-1]
For each node, the output gives the nearest ancestor whose value is coprime with that node's value, or -1 when none exists.

Constraints

  • nums.length == n
  • 1 <= nums[i] <= 50
  • 1 <= n <= 10^5
  • edges.length == n - 1
  • edges[j].length == 2
  • 0 <= uj, vj < n
  • uj != vj

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