用Python实现一个简单的算术游戏

#!/usr/bin/env python     from operator import add, sub  from random import randint, choice     ops = {'+': add, '-':sub}  #定义一个字典  MAXTRIES = 2     def doprob():      op = choice('+-')      #用choice从'+-'中随意选择操作符      nums = [randint(1,10) for i in range(2)]      #用randint(1,10)随机生成一个1到10的数,随机两次使用range(2)      nums.sort(reverse=True)      #按升序排序      ans = ops[op](*nums)      #利用函数      pr = '%d %s %d = ' % (nums[0], op, nums[1])      oops = 0      #oops用来计算failure测试,当三次时自动给出答案      while True:          try:              if int(raw_input(pr)) == ans:                  print 'correct'                  break              if oops == MAXTRIES:                  print 'answer\n %s%d' % (pr, ans)                  break              else:                  print 'incorrect... try again'                  oops += 1          except (KeyboardInterrupt, EOFError, ValueError):              print 'invalid ipnut... try again'  def main():      while True:          doprob()          try:              opt = raw_input('Again? [y]').lower()              if opt and opt[0] == 'n':                  break          except (KeyboardInterrupt, EOFError):              break     if __name__ == '__main__':      main()