mirror of
https://github.com/TheAlgorithms/Ruby
synced 2024-12-28 22:24:14 +01:00
23 lines
595 B
Ruby
23 lines
595 B
Ruby
=begin
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Searches through a list for a value in O(log(n)) time.
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The list must be sorted.
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=end
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def binary_search(array, key)
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front = 0
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back = array.length - 1
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while front <= back
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middle = (front + back) / 2
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return middle if array[middle] == key
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key < array[middle] ?
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back = middle - 1 : front = middle + 1
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end
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nil
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end
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puts "Enter a sorted space-separated list:"
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arr = gets.chomp.split(' ').map(&:to_i)
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puts "Enter the value to be searched:"
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value = gets.chomp.to_i
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puts binary_search(arr, value) != nil ?
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"Found at index #{binary_search(arr, value)}" :
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"Not found"
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