Sort Colors

	/**
	 * Given an array with n objects colored red, white or blue, sort them
so
	 * that objects of the same color are adjacent, with the colors in the
order
	 * red, white and blue.
	 * 
	 * Here, we will use the integers 0, 1, and 2 to represent the color
red,
	 * white, and blue respectively.
	 * 
	 * Note: You are not suppose to use the library's sort function for
this
	 * problem.
	 * 
	 * click to show follow up.
	 * 
	 * Follow up: A rather straight forward solution is a two-pass
algorithm
	 * using counting sort. First, iterate the array counting number of
0's,
	 * 1's, and 2's, then overwrite array with total number of 0's, then
1's and
	 * followed by 2's.
	 * 
	 * Could you come up with an one-pass algorithm using only constant
space?
	 * 
	 * */
	
	/*
     * 0 - red
     * 1 - white
     * 2 - blue
     *
     *  red | white | blue
     *
     * e.g.
     *      1 0 2 1 0 2 0
     *      0 0 2 1 0 2 1
     *      0 0 1 1 0 2 2      
     *      0 0 0 1 1 2 2
     *      
     */