2Max drill

# 2Max drill

function DigitsOf(N::Int64)
    X = split(string(N), "")
    return map(x -> parse(Int64, x), X)
end

function FindIntsWithEqualSum(x::Array{Int64, 1})
    n = length(x)
    mnc = div(n * (n-1), 2)
    z = Array{Int64}(undef, n)
    for i = 1:n; z[i] = sum(DigitsOf(x[i])); end
    X = Array{Int64}(undef, mnc, 2)
    c = 0

    for i = 1:(n-1)
        for j = (i+1):n
            if z[i] == z[j]; c += 1; X[c,:] = [x[i], x[j]]; end
        end
    end

    return X[1:c,:], c
end

function main(x::Array{Int64, 1})::Int64
    n = length(x)
    X, c = FindIntsWithEqualSum(x)

    if c == 0
        return -1
    else
        return maximum(sum(X, dims = 2))
    end
end