简单的加减法数学游戏

from random import randint, choice

def add(x, y):
return x + y

def sub(x, y):
return x - y

def exam():
cmds = {‘+’: add, ‘-‘: sub}
nums = [randint(1, 100) for i in range(2)]
nums.sort(reverse=True)
op = choice(‘+-‘)
result = cmdsop
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('Wrong Answer!')
    counter += 1
else:
    print('The Answer:')
    print('%s%s' % (prompt, result))

if name == ‘main‘:
while True:
exam()
try:
yn = input(‘Continue(y/n)? ‘).strip()[0]
except IndexError:
continue
except (KeyboardInterrupt, EOFError):
yn = ‘n’

    if yn in 'nN':
        print('\nBye-bye')
        break