39 lines
649 B
Julia
39 lines
649 B
Julia
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function solution(n_max)
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longest_cycle = 0
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cycle_length = 0
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for i ∈ 2:n_max
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if check_if_finite(i)
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continue
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end
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println(i)
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n = 1
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p = i
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while ~(Set(digits(p)) == Set(9))
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p *= i
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@info n += 1
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end
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if n > cycle_length
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longest_cycle = i
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cycle_length = n
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end
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end
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return longest_cycle, cycle_length
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end
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function check_if_finite(n)
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print("checking ")
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println(n)
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k = n
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while k%2 == 0
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k = div(k, 2)
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end
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while k%5 == 0
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k = div(k, 5)
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end
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return k == 1
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end
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