Editorial for DMOPC '14 Contest 5 P6 - Nia and Dominoes
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Submitting an official solution before solving the problem yourself is a bannable offence.
Submitting an official solution before solving the problem yourself is a bannable offence.
Author:
Since is really big, we want to find an algorithm that uses
, which is just the length of the input (still on the order of
!). The given sequence is periodic with a maximal period of
, so we can use a cycle-finding algorithm to find the preperiod and period, and take the input number mod the period, and use some brute force to find the answer for that value.
Time Complexity:
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