Contest: Task: Related: TaskB

Score : $100$ points

Snuke has a grid consisting of three squares numbered $1$, $2$ and $3$.
In each square, either `0`

or `1`

is written. The number written in Square $i$ is $s_i$.

Snuke will place a marble on each square that says `1`

.
Find the number of squares on which Snuke will place a marble.

- Each of $s_1$, $s_2$ and $s_3$ is either
`1`

or`0`

.

Input is given from Standard Input in the following format:

$s_{1}s_{2}s_{3}$

Print the answer.

101

2

- A marble will be placed on Square $1$ and $3$.

000

0

- No marble will be placed on any square.