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Description

Little K sent a binary string of length $8$ to Little P to play a number game. Little P wants to know how many times the character $1$ occurs in the string.

Note: A binary string is a string in which each character is either $0$ or $1$. E.g., "101" (withuot quotes) is a binary string of length $3$.

Input Format

The input has only one line consisting of a binary string $s$ of length $8$.

Output Format

Print the number of times the character $1$ occurs in $s$.

00010100

2

Constraints

For $20\%$ of the data, all characters in the string are $0$s.
For $100\%$ of the data, the input may contain both $0$s and $1$s. The length of the string is $8$.