Impossible n’est pas français

Posted by rk700 on July 2, 2014

http://www.wechall.net/challenge/impossible/index.php
这道题要求在6秒内分解一个超级大的整数,所以标题的名字都是”impossible”

这道题比较奇怪的一个地方是,如果你输入了错误的答案,他会把正确的答案告诉你,而这按理来说并不需要。于是从这里入手,发现即使答错,问题的整数还是没有变,这就给了我们再次尝试的机会。也就是说,先得到正确答案,然后在6秒之内再回答就行。

下面是python代码

#!/usr/bin/env python2

import urllib
import urllib2
import re

if __name__ == "__main__":
url = "http://www.wechall.net/challenge/impossible/index.php?request=new_number"
req = urllib2.Request(url)
req.add_header('cookie','WC=7436562-11403-u5AFYCNQVEgMepLw')
response = urllib2.urlopen(req)

url = "http://www.wechall.net/challenge/impossible/index.php"
values = {'solution':1, 'cmd':'Send'}
data = urllib.urlencode(values)
req = urllib2.Request(url, data)
req.add_header('cookie','WC=7436562-11403-u5AFYCNQVEgMepLw')
response = urllib2.urlopen(req)
content = response.read()

p = re.compile('Correct would have been "(\d*)&')
sol = p.search(content).group(1)
print sol

values = {'solution':sol, 'cmd':'Send'}
data = urllib.urlencode(values)
req = urllib2.Request(url, data)
req.add_header('cookie','WC=7436562-11403-u5AFYCNQVEgMepLw')
response = urllib2.urlopen(req)
content = response.read()
print content