Problem:
Score : 100 points

Problem Statement

You are given two integers A and B as the input. Output the value of A + B.

However, if A + B is 10 or greater, output error instead.

Constraints

A and B are integers.

1 ≤ A, B ≤ 9

Input

Input is given from Standard Input in the following format:

A B

Output

If A + B is 10 or greater, print the string error (case-sensitive); otherwise, print the value of A + B.

Sample Input 1

6 3

Sample Output 1

9

Sample Input 2

6 4

Sample Output 2

error

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

function main()
    a,b=parseMap(split(readline()))
    println(ifelse(a+b>=10,"error",a+b))
end
main()