Problem:
Score : 100 points

Problem Statement

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.

Constraints

Each of s_1, s_2 and s_3 is either 1 or 0.

Input

Input is given from Standard Input in the following format:

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

Output

Print the answer.

Sample Input 1

101

Sample Output 1

2

A marble will be placed on Square 1 and 3.

Sample Input 2

000

Sample Output 2

0

No marble will be placed on any square.

Solution in Julia (0.5.0) (judge verdict: Accepted)

parseInt(x::String) = parse(Int, x)
parseInt(x::SubString{String}) = parse(Int, x)
parseInt(x::Char) = parse(Int, x)
parseInt(x::Float64) = trunc(Int, x)
parseFloat(x::String) = parse(Float64, x)
parseFloat(x::Int) = trunc(Float64, x)
parseMap(x::Array{SubString{String},1}) = map(parseInt, x)

function main()
    println(count(i->i=='1',chomp(readline())))
end
main()