23 lines
758 B
JavaScript
23 lines
758 B
JavaScript
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function binary_Search(items, value){
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var firstIndex = 0,
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lastIndex = items.length - 1,
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middleIndex = Math.floor((lastIndex + firstIndex)/2);
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while(items[middleIndex] != value && firstIndex < lastIndex)
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{
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if (value < items[middleIndex])
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{
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lastIndex = middleIndex - 1;
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}
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else if (value > items[middleIndex])
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{
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firstIndex = middleIndex + 1;
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}
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middleIndex = Math.floor((lastIndex + firstIndex)/2);
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}
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return (items[middleIndex] != value) ? -1 : middleIndex;
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}
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var items = [1, 2, 3, 4, 5, 7, 8, 9];
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console.log(binary_Search(items, 1));
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console.log(binary_Search(items, 5));
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