21点游戏，命令行的，面像过程的写法。

ruby 的写法以后再试试。

# this is game 21 point
# 操作命令符 空没有操作，n下一步，抽牌；w亮牌结束；l认输
$ope = ''
$prompt = '>'
$x1 = 0
$x2 = 0
$x3 = 0
$pc = 0
$u1 = 0
$u2 = 0
$u3 = 0
$over = ''

def out_main(a = 0, b=0, c=0, pc = 0, us1=0, us2=0, us3=0)
  puts "21 point Game          "
  puts "        -- wide288 author"
  puts
  puts "  PC is keys           "
  if pc == 0
    puts "  *  *  *              "
  else
    puts "  %d  %d  %d              "% [a, b, c]
  end

  puts
  puts "  user is keys         "
  puts " %d %d %d              " % [us1, us2, us3]
  puts Time.new
  puts " n 抽牌; w 亮牌; l 认输; x 退出;"
end

#主线程运行
def main()
  while $ope != 'x'
    system 'clear'
    out_main($x1, $x2, $x3, $pc, $u1, $u2, $u3)
    if 'w' != $ope
      print $prompt
      $ope = STDIN.gets.chomp()
    end
    if 'x' == $ope
      break
    end
    if 'l' == $ope
      puts "I throw up."
      break
    end
    if 'n' == $ope
      number = rand(1..10)
      if 0 != number
        puts number
        if $x1 == 0
          $x1 = number
        elsif $x2 == 0
          $x2 = number
        elsif $x3 == 0
          $x3 = number
        end
      end

      number = rand(1..9)
      if 0 != number
        puts number
        if $u1 == 0
          $u1 = number
        elsif $u2 == 0
          $u2 = number
        elsif $u3 == 0
          $u3 = number
        end
      end
    end

    if 'w' == $ope
      #system "clear"
      $pc = 1
      pcsum = 21 - ($x1+$x2+$x3)
      usersum = 21 - ($u1+$u2+$u3)
      puts "%d %d %d pc sum is - 21 =  %d" % [$x1, $x2, $x3, pcsum]
      puts "%d %d %d user sum is - 21 = %d" % [$u1, $u2, $u3, usersum]
      if usersum >= pcsum
        puts "pc win"
      else
        puts "User Win!!!"
      end
      #out_main($x1, $x2, $x3, $pc, $u1, $u2, $u3)
      break
    end
  end
end

# main thread run
main()