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Pudding Monster but on a tree :))
By Sammmmmmm, history, 6 weeks ago, In English

Given a tree of n vertices, count the number of ways to choose a connected subgraph of the tree so that all the vertices in that

subgraph consists of consecutive integers when sorted. Thanks!

N <= 3e5

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6 weeks ago, # |
← Rev. 2   Vote: I like it +10 Vote: I do not like it

let mx[i] = largest vertice on the path ($$$i, i + 1$$$).

mn[i] = smallest vertice on the path ($$$i, i + 1$$$).

calculate number of pairs ($$$l < r$$$) such that $$$r - l$$$ = max(mx[ $$$l$$$ ..($$$r - 1$$$)]) — min(mn[ $$$l$$$ ..($$$r - 1$$$)]);

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6 weeks ago, # |
← Rev. 7   Vote: I like it +14 Vote: I do not like it

incorrect solution

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