Graph Theory37 sections · 1633 units
Open in Course

Problem - Planets Queries I

(CSES 1750)

You are given nn planets where each planet has a teleporter to another planet. Answer qq queries: starting from planet xx, where are you after kk steps? kk can be up to 10910^9. This is the direct application of binary lifting. Each planet is a node, and the teleporter defines f(x)f(x).

Simulating 10910^9 steps times out. I'll show you how to build the jump table and answer queries efficiently. The preprocessing takes O(nlog⁡n)O(n \log n), but each query is O(log⁡k)O(\log k).

Space complexity is O(nlog⁡n)O(n \log n) for the data structures used.