Quick Password Generator

#! /bin/env ruby

if ARGV[0] && ARGV[0].respond_to?(:chr)

    print "[*] Quick Password Generator [*]\n\n"
    print "    "

    ARGV[0].to_i.times do |x|
        arr = [rand(48..57),rand(65..90),rand(97..122)].map(&:chr)
        print arr[rand(0...arr.length)]
    end

    print "\n\n[*] Complete.\n"
else
    print "[*] ERROR: No length supplied.\n"
    print "[*] USAGE: ruby quick-gen.rb <length>\n"
end