#=
Created on 16 Aug 2021

@author: David Doblas Jiménez
@email: daviddoji@pm.me

Solution for Problem 26 of Project Euler
https://projecteuler.net/problem=26
=#

function Problem26()
    #=
    A unit fraction contains 1 in the numerator. The decimal representation
    of the unit fractions with denominators 2 to 10 are given:

        1/2	= 	0.5
        1/3	= 	0.(3)
        1/4	= 	0.25
        1/5	= 	0.2
        1/6	= 	0.1(6)
        1/7	= 	0.(142857)
        1/8	= 	0.125
        1/9	= 	0.(1)
        1/10 = 	0.1

    Where 0.1(6) means 0.166666..., and has a 1-digit recurring cycle.
    It can be seen that 1/7 has a 6-digit recurring cycle.

    Find the value of d < 1000 for which 1/d contains the longest recurring
    cycle in its decimal fraction part.
    =#
    cycle_length = 0
    number_d = 0
    for number in 3:2:999
        if number % 5 == 0
            continue
        end
        p = 1
        while (big(10)^p % number) != 1
            p += 1
        end
        if p > cycle_length
            cycle_length, number_d = p, number
        end
    end
    return number_d
end


println("Time to evaluate Problem 26:")
@time Problem26()
println("")
println("Result for Problem 26: ", Problem26())