简单的加减法

编写math_game.py脚本，实现以下目标：

1. 随机生成两个100以内的数字
2. 随机选择加法或是减法
3. 总是使用大的数字减去小的数字
4. 如果用户答错三次，程序给出正确答案

   from random import randint, choice
   
   def exam():
       counter = 0
       while counter < 3:
           nums = [randint(1, 100) for i in range(2)]
           nums.sort(reverse=True)
           op = choice('+-')
           if op == '-':
               result = nums[0] - nums[1]
           else:
               result = nums[0] + nums[1]
           prompt = '%s %s %s =' % (nums[0], op, nums[1])
           answer = int(input(prompt))
           if answer == result:
               print('very Good')
           else:
               print('33[31;1msorry,You are wrong33[0m')
               counter += 1
   
   
   def main():
       while True:
           yn = input('Continue:/y/n ?').strip()[0]  # 去除空白 然后取第一位
           if yn in 'nN':
               print('
   Bye-bye')
               break
           exam()
   
   
   if __name__ == '__main__':
       main()

   from random import randint, choice
   
   
   def add(x,y):
       return x-y
   def sum(x,y):
       return x+y
   
   def exam():
   
           cmds = {'-':add,'+':sum}
           nums = [randint(1, 100) for i in range(2)]
           nums.sort(reverse=True)
           op = choice('+-')
           result = cmds[op](*nums)
           # print(*nums)
           # if op == '-':
           #     result = add(nums[0],nums[1])
           # else:
           #     result = sum(nums[0],nums[1])
           prompt = '%s %s %s =' % (nums[0], op, nums[1])
   
           counter = 0
           while counter < 3:
               try:
                   answer = int(input(prompt))
               except:
                   print()
                   continue
               if answer ==result :
                   print('very Good')
                   break
               else:
                   print('33[31;1msorry,You are wrong33[0m')
                   counter += 1
           else:
               print('%s %s' %(prompt,result))
   
   
   def main():
   
       while True:
           exam()
           try:
               yn = input('Continue:/y/n ?').strip()[0]  # 去除空白 然后取第一位
           except IndexError:
                continue
           except (KeyboardInterrupt,EOFError):
               yn = 'n'
   
           if yn in 'nN':
               print('
   Bye-bye')
               break
   
   
   
   if __name__ == '__main__':
       main()