Single Number II 

	/**
	 * Given an array of integers, every element appears three times except
for one. Find that single one.
	 * 
	 * Note: Your algorithm should have a linear runtime complexity. Could
you implement it without using extra memory?
	 * 
	 * */

	/**
	 * 
	 * 2, 2, 2, 4,
	 * 
	 * 2 - 010 
	 * 4 - 100
	 * 
	 * 1st bit: 0 + 0 + 0 + 0 = 0 % 3 = 0 
	 * 2nd bit: 1 + 1 + 1 + 0 = 3 % 3 = 0 
	 * 3nd bit: 0 + 0 + 0 + 1 = 1 % 3 = 1
	 * 
	 * 100 = 4
	 * 
	 * */