javascript binarySearch

binary_search.js

Array.prototype.binarySearch = function(key) {
	var low = 0,
		high = this.length - 1;

	while (low <= high) {
		var mid = (low + high) >>> 1;
		var midVal = this[mid];

		if (midVal < key)
			low = mid + 1;
		else if (midVal > key)
			high = mid - 1;
		else
			return mid; // key found
	}

	return -(low + 1);  // key not found.
};