The following algorithm can be used to encode a sequence of characters s:
 Find any palindrome of even length in s. A palindrome is a string that reads the same forward and backward. If there are no palindromes of even length, go to step 3.
 Remove the last half of the selected palindrome from s. For example, if the palindrome is "0110", remove the "10". Go to step 1.
 Print the remaining sequence of characters.
Note that the resulting sequence is not necessarily unique since there may be multiple palindromes to choose from in step 1.
Given a String s containing only the digits '0' and '1', return the length of the shortest possible string that can result from applying the above algorithm to s.
