https://www.interviewbit.com/problems/max-edge-queries/
Someone please suggest a idea or share some resource that will help me to solve this problem.
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https://www.interviewbit.com/problems/max-edge-queries/
Someone please suggest a idea or share some resource that will help me to solve this problem.
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You need standart LCA. For each vertex $$$a$$$ you can calculate $$$find(a, count)$$$ — the maximum weigth of $$$count$$$ edges if you go from $$$a$$$ up to the root. So if you know that $$$LCA(x, y) = z$$$ and $$$dist(x, z) = l, dist(y, z) = r$$$, the answer is $$$max(find(x, l), find(y, r))$$$.
you can solve queries offline using some precomputation
first calculate $$$LCA(u, v) = L$$$ for each $$$query$$$
calculate the max edge between each $$$(L, u)$$$ and $$$(L, v)$$$ pair you can do this in $$$O(n + q*log(n))$$$ using segment tree best i know, may be there is a better way to this
after doing above two steps you know the $$$ans$$$ for $$$(L, u)$$$ and $$$(L, v)$$$
$$$ans$$$ for query $$$(u, v)$$$ is $$$max(ans(L, u), ans(L, v))$$$
resources LCA segment tree
Precompute binary lifting, and compute like a sparse table on the tree, for each node U, calculate the maximal edge 2^i up, then for each query compute the LCA, and compute the maximum from u -> LCA and from v -> LCA