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 (1.4.0) (judge verdict: Accepted)

ParseInt(x) = parse(Int,x)
ParseMap(x::Array{SubString{String},1}) = map(ParseInt,x)
function main()
    a = chomp(readline())
    cnt = 0
    if a[1] == '1'
        cnt += 1
        end
        if a[2] == '1'
            cnt += 1
            end
            if a[3] == '1'
                cnt += 1
                end
                println(cnt)
end
main()