bhikkhu's blog

geometric series problem

By bhikkhu, history, 8 years ago, In English

http://codeforces.net/contest/758/problem/F

Guys can anybody explain why the upper bounds for x and y for the ratio d = x/y is n-1 th root of 'r'?

I know it myself but I want to know what other coders think about it.

So basically explain why x <= power(r, 1 / (n — 1)) and y <= power(r, 1 / (n — 1))?

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8 years ago, # |
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Auto comment: topic has been updated by bhikkhu (previous revision, new revision, compare).

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8 years ago, # |
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Assuming you're talking about the variables x and y defined in the editorial, for y we have:

b × yn - 1 ≤ r

The case for x is the same if you just replace y with x.

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