js二分查找

为了适配业务，js写了个二分查找。

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function binarySearch(items,value){
	var startIndex=0,
	stopIndex=items.length-1,
	middle=Math.floor((stopIndex+startIndex)/2);
	while(items[middle]!=value && startIndex<stopIndex){
		if(value<items[middle]){
			stopIndex=middle-1;
		}else if(value>items[middle]){
			startIndex =middle+1;
		}
		middle=Math.floor((stopIndex+startIndex)/2)
	}
	return (items[middle]!=value) ? -1 : middle
}
console.log(binarySearch([1,2,3,4,5,6],6))