Squares of a Sorted Array

# Squares of a Sorted Array

function MergeSortedLists(x::Array{Int64, 1}, y::Array{Int64, 1})
    nx = length(x)
    ny = length(y)
    n = nx + ny
    z = Array{Int64}(undef, n)
    c = 1
    cx = 1
    cy = 1

    if x[1] < y[1]
        z[1] = x[1]
        cx += 1
    else
        z[1] = y[1]
        cy += 1
    end

    while c < n
        c += 1

        if x[cx] < y[cy]
            z[c] = x[cx]
            cx += 1

            if cx > nx
                c += 1
                z[c:end] = y[cy:end]
                c = n
            end
        else
            z[c] = y[cy]
            cy += 1

            if cy > ny
                c += 1
                z[c:end] = x[cx:end]
                c = n
            end
        end
    end

    return z
end

function main(z::Array{Int64, 1})
    x = z[z.<0] # list of negative numbers
    y = z[z.>=0] # list of positive numbers
    x .^= 2
    y .^= 2
    return MergeSortedLists(reverse(x), y)
end