Huseyn has a string consisting of 0 and 1. He had nothing to do and came up with the following game. Huseyn can do the next operation with the string:
append 0 from the left end, and 1 from the right end;
append 0 from the right end, and 1 from the left;
You are given a string after Huseyn completed all his operations (the number of performed operations can be 0). Find the smallest possible length that string could have initially.
For example, from the string 010, you can get 00101 or 10100.
One string of length no more than 105, consisting of 0 and 1.
Print the smallest possible length of a string that Huseyn had originally.