Reverse an array without using another array. This method is called Temporary Swap and it only runs for half of the array.

ReverseArray.js

function reverse(arr)
{
    var left = null;
    var right = null;
    var length = arr.length;
    for (left = 0; left < length / 2; left += 1)
    {
        right = length - 1 - left;
        var temporary = arr[left];
        arr[left] = arr[right];
        arr[right] = temporary;
    }
    return arr;
}