mirror of
https://github.com/TheAlgorithms/Ruby
synced 2024-12-27 21:58:57 +01:00
42 lines
1 KiB
Ruby
42 lines
1 KiB
Ruby
# Works only on sorted arrays.
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# Finding element by creating step in array and jump ahead by fixed steps and finding element using linear search inside that steped array.
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# Time Complexity: O(√n)
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def jump_search(arr, x)
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n = arr.length
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# Finding block size to be jumped
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step = Math.sqrt(n)
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prev = 0
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# Finding the block where element is
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# present (if it is present)
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while arr[[step, n].min - 1] < x
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prev = step
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step += Math.sqrt(n)
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return -1 if prev >= n
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end
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# Doing a linear search for x in block
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# beginning with prev.
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while arr[prev] < x
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prev += 1
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# If we reached next block or end of
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# array, element is not present.
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return -1 if prev == [step, n].min
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end
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# If element is found
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return prev if arr[prev] == x
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-1
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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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index = jump_search(arr, value)
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puts index == -1 ? 'Element not found' : "Number #{value} is at #{index}"
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