Hello!
Given a binary tree, find a** maximum path for each node**.
Hope to get an optimal solution Input- N=6
edges= 1->2,2->3,1->4,4->5,4->6
output= 2 3 4 3 4 4
Thanks in advance!
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Hello!
Given a binary tree, find a** maximum path for each node**.
Hope to get an optimal solution Input- N=6
edges= 1->2,2->3,1->4,4->5,4->6
output= 2 3 4 3 4 4
Thanks in advance!
Название |
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You can solve this problem using DP on trees, check this tutorial
solition in O(n log n)
lets find the answer for node V. V has O(logN) nodes in path from V to root. Let U — node in this path. then also let's find for each V max_d[V] — max len from V to some node in subtree of V.
let's try to update the answer for V. there's a exactly one son of U, who is in the path from V to root, let it be Z. then there's the algorithm to find the ans for V, if U is known.
i think it's pretty obvious why it works. so then whole alg is this: