Protap_Ghose's blog

By Protap_Ghose, history, 9 years ago, In English

Problem link : (http://codeforces.me/problemset/problem/166/E)

How to solve this problem log(n) with binary exponentiation of some 2 × 2 matrix into power n. Needs some explanation in this problem .Thanks in advance.

Sorry for bad english.

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9 years ago, # |
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Not sure how to do it with a 2x2 matrix, but I solved this problem by exponentiating a 4x4 adjacency matrix. I'm guessing the 2x2 solution somehow exploits the symmetry in the tetrahedron.