Write a function that takes two sorted lists of numbers and merges them into a single sorted list.

mergeSortedArrays.js

var assert = require('assert');

function sortMerged(lOne, lTwo) {
	return lOne.reduce(function (sortedList, num, index) {
		var position = findPositionBinary(sortedList, num);
		sortedList.splice(position, 0, num);
		return sortedList;
	}, lTwo);
}

/*function findPosition(sList, num) { //linear search time
	var m = 0;
	for (m; m < sList.length; m++) {
		if (sList[m] >= num) {
			return m;
		}
	};
	return m;
}*/

//optimization
function findPositionBinary(sList, num, offset) {
	var middle = Math.floor(sList.length / 2),
		middleVal = sList[middle],
		ending = sList.length === 1;
	offset = offset || 0;
	if (middleVal > num) {
		if (ending || middle - 1 === -1) {
			return middle + offset;
		}
		return findPositionBinary(sList.slice(0, middle), num) + offset;
	} else if (middleVal < num) {
		if (ending || middle + 1 === sList.length ) {
			return middle + 1 + offset;
		}
		return findPositionBinary(sList.slice(middle, sList.length), num, middle) + offset;
	} else {
		return middle + offset;
	}
}

var testArray = [1, 2, 3, 4, 5, 6, 7,8 , 9];
assert.equal(findPositionBinary(testArray, 0), 0);
assert.equal(findPositionBinary(testArray, 5), 4);
assert.equal(findPositionBinary(testArray, 8), 7);
assert.equal(findPositionBinary(testArray, 1.5), 1);
assert.equal(findPositionBinary(testArray, 2.5), 2);
assert.equal(findPositionBinary(testArray, 3.5), 3);
assert.equal(findPositionBinary(testArray, 6.5), 6);
assert.equal(findPositionBinary(testArray, 9.5), 9);

console.log(sortMerged([0, 0.3, 2, 100], [1, 4, 5]));