Project Euler/63: Difference between revisions
From charlesreid1
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==Solution Technique== | ==Solution Technique== | ||
This one is almost embarrassingly easy... | |||
To check if a number <math>a^b</math> is <math>b</math> digits, we can take <math>\log_{10}(b)</math> and if the value, rounded up, is <math>b</math>, our criteria is met. | |||
For this particular problem, we can stop at <math>n=25</math>, since <code>ceil(log10(9**25)) = 25</code> | |||
==Code== | ==Code== | ||
Revision as of 10:29, 8 January 2018
Problem Statement
How many n-digit positive integers exist which are also an nth power?
Link: https://projecteuler.net/problem=63
Solution Technique
This one is almost embarrassingly easy...
To check if a number $ a^b $ is $ b $ digits, we can take $ \log_{10}(b) $ and if the value, rounded up, is $ b $, our criteria is met.
For this particular problem, we can stop at $ n=25 $, since ceil(log10(9**25)) = 25
Code
Link: https://charlesreid1.com:3000/cs/euler/src/master/scratch/Round2_050-070/063
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