Problem Statement

You are given a sequence?

A=(A 0 ,A 1 ,…,A 63 ) of length 64 consisting of 0 and 1.Find A 0 2 0 +A 1 2 1 +?+A 63 2 63

?Constraints

A i? is 0 or 1.

Input

The input is given from Standard Input in the following format:

A 0A 1… A 63?

Output

Print the answer as an integer.

Sample Input 1?

1 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Sample Output 1?

13

A 0 2 0 +A 1 2 1 +?+A 63 2 63 =2 0 +2 2 +2 3 =13.

Sample Input 2?

1 0 1 0 1 0 0 0 0 1 0 0 1 1 0 1 1 1 1 0 0 0 1 0 0 1 1 1 1 1 1 0 0 0 0 1 0 1 0 1 0 1 1 1 1 0 0 1 1 0 0 0 0 1 0 1 0 1 0 1 0 0 0 0

Sample Output 2?

766067858140017173

用int或者long或者double都會存在溢出的情況，所以用java的bigInteger處理，當然也可以位運算，只是我不會了。。。