import requests
import re
import time
url = 'http://76561f35-2f9d-46ca-a58e-e4d944ebde9c.node4.buuoj.cn:81/index.php'
s = requests.session()
r = s.get(url)
while True:
calc = re.search('<br>(\d*)(-|\+)(\d*)<br>', r.text.replace(' ',''))
ans = eval(calc.group().replace('<br>',''))
data = {
'answer': ans
}
r = s.post(url, data=data)
print(r.text)
time.sleep(0.1)
