Basic Password Generator

LCC = "qwertyuiopasdfghjklzxcvbnm"
UCC = uppercase(LCC)
NC = "1234567890"

function gp(L::Int64 = 10, ULC::Bool = true, UUC::Bool = true, UNC::Bool = true)
    if !(ULC||UUC||UNC); println("At least one of the requirements needs to be true!"); return ""; end
    if L <= 8; println("Passwords of this size can be easily cracked! Please pick a larger number of characters."); return ""; end
    PC = ""
    if ULC; PC = string(PC, LCC); end
    if UUC; PC = string(PC, UCC); end
    if UNC; PC = string(PC, NC); end
    n = length(PC)
    OK = false
    pw = [' ']

    while !OK
        pw = Array{Char}(undef, L)
        OK_LCC = OK_UCC = OK_NC = false

        for i = 1:L
            r = rand(1:n)
            pw[i] = PC[r]

            if ULC
                if PC[r] in LCC; OK_LCC = true; end
            else
                OK_LCC = true
            end

            if UUC
                if PC[r] in UCC; OK_UCC = true; end
            else
                OK_UCC = true
            end

            if UNC
                if PC[r] in NC; OK_NC = true; end
            else
                OK_NC = true
            end
        end

        OK = OK_LCC && OK_UCC && OK_NC
    end

    return join(pw,"")
end