Ballista's blog

By Ballista, history, 5 years ago, In English

Given a Graph $$$D$$$ of $$$N$$$ nodes, where each node $$$i$$$ has $$$C_i$$$ coins attached with it. You have to choose a subset of nodes such that no two adjacent nodes(i.e. nodes connected directly by an edge) are chosen and sum of coins attached with nodes in chosen subset is maximum.

For a tree this is a famous DP on Tree problem ( solution for Tree version here: https://codeforces.me/blog/entry/20935 -> Problem 1 ). Can we extend the DP on trees logic to solve it for a general graph. If not how can should I approach it?

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By Ballista, history, 5 years ago, In English

You are given N intervals and Q ranges. For each range you have to count number of intervals lying completely inside the range.

How can we do this query per range in O(log n)?

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