зеркало из https://github.com/mozilla/gecko-dev.git
18 строки
532 B
CoffeeScript
18 строки
532 B
CoffeeScript
# Uses a binary search algorithm to locate a value in the specified array.
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window.binary_search = (items, value) ->
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start = 0
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stop = items.length - 1
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pivot = Math.floor (start + stop) / 2
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while items[pivot] isnt value and start < stop
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# Adjust the search area.
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stop = pivot - 1 if value < items[pivot]
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start = pivot + 1 if value > items[pivot]
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# Recalculate the pivot.
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pivot = Math.floor (stop + start) / 2
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# Make sure we've found the correct value.
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if items[pivot] is value then pivot else -1 |