Problem Statement

You are given a sequence 

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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都会存在溢出的情况，所以用java的bigInteger处理，当然也可以位运算，只是我不会了。。。