48 lines
1.0 KiB
Julia
48 lines
1.0 KiB
Julia
#=
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Created on 25 Aug 2021
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@author: David Doblas Jiménez
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@email: daviddoji@pm.me
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Solution for Problem 30 of Project Euler
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https://projecteuler.net/problem=30
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=#
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using BenchmarkTools
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function power_digit_sum(pow, n)
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s = 0
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while n > 0
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(n, r) = divrem(n, 10)
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s += r^pow
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end
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return s
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end
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function Problem30()
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#=
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Surprisingly there are only three numbers that can be written as the sum
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of fourth powers of their digits:
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1634 = 1^4 + 6^4 + 3^4 + 4^4
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8208 = 8^4 + 2^4 + 0^4 + 8^4
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9474 = 9^4 + 4^4 + 7^4 + 4^4
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As 1 = 14 is not a sum it is not included.
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The sum of these numbers is 1634 + 8208 + 9474 = 19316.
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Find the sum of all the numbers that can be written as the sum of fifth
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powers of their digits.
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=#
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ans = sum(i for i in 2:1_000_000 if i == power_digit_sum(5, i))
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return ans
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end
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println("Time to evaluate Problem $(lpad(30, 3, "0")):")
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@btime Problem30()
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println("")
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println("Result for Problem $(lpad(30, 3, "0")): ", Problem30())
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