Counting on a Tree

CodeChefRating 2841Open on judge ↗

You are given an unrooted tree with N nodes, numbered from 1 to N. Each edge of the tree has a positive integer, associated with it. Your goal is to calculate the number of unordered pairs (S, T) of tree's nodes such that the greatest common divisor of all the integers associated with the edges of the path between S and T is equal to one. Of course, we consider only the pairs where S isn't equal t

HINT LADDERno hints yet

L1 Observation

L2 Technique

L3 Approach

L4 Pseudo-code

🔒

L5 Full solution

L5 unlocks only if you insist twice

solution.cppC++17

CodeSearch Tutor

Hints, not spoilers — it won’t hand over the full solution unless you insist.

voice by Sarvam AI