#！/usr/bin/env python

 # -*- coding:utf-8 -*-

 import random

 temp =''

 for i in range(6):

     num = random.randrange(0,4)

     if num ==3 or num == 1:

         rad2 = random.randrange(0,10)

         temp = temp + str(rad2)

     else:

         rad1 = random.randrange(65,91)

         c1 = chr(rad1)

         temp = temp + c1

 print(temp)