Problem:
Score : 300 points

Problem Statement

You are given three integers A, B and C. Find the minimum number of operations required to make A, B and C all equal by repeatedly performing the following two kinds of operations in any order:

Choose two among A, B and C, then increase both by 1.

Choose one among A, B and C, then increase it by 2.

It can be proved that we can always make A, B and C all equal by repeatedly performing these operations.

Constraints

0 \leq A,B,C \leq 50

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the minimum number of operations required to make A, B and C all equal.

Sample Input 1

2 5 4

Sample Output 1

2

We can make A, B and C all equal by the following operations:

Increase A and C by 1. Now, A, B, C are 3, 5, 5, respectively.

Increase A by 2. Now, A, B, C are 5, 5, 5, respectively.

Sample Input 2

2 6 3

Sample Output 2

5

Sample Input 3

31 41 5

Sample Output 3

23

Solution in Julia (0.5.0) (judge verdict: Wrong Answer)

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()
    a,b,c=sort(parseMap(split(readline())))
    ans=0
    if a%2==c%2
        ans+=div(c-a,2)
        a=c
    else
        ans+=div(c-a-1,2)
        a=c-1
    end
    if b%2==c%2
        ans+=div(c-b,2)
        b=c
    else
        ans+=div(c-b-1,2)
        b=c-1
    end
    if a==c && b<c
        ans+=2
    elseif a<c && b<c
        ans+=1
    end
    println(ans)
end
main()