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 1 #coding:utf-8
 2 #python 2.7
 3 import urllib
 4 import re
 5 
 6 #1. 第一层base64
 7 with open(‘base64.txt‘) as f:
 8     cipher1 = f.read()
 9 plain1 = cipher1.decode(‘base64‘)
10 # print plain1, type(plain1)
11 
12 #2. 第二层，根据plain1的形式（0-7的整数），推测为8进制加密
13 cipher2 = plain1
14 cipher2 = re.findall(r‘\d+‘, cipher2)
15 # print cipher2
16 plain2 = ‘‘
17 for i in cipher2:
18     plain2 += chr(int(i, 8))
19 # print plain2
20 
21 #3. 第三层，根据plain2的形式（\xdd），推测为16进制加密
22 cipher3 = plain2
23 cipher3 = re.findall(r‘\d+‘, cipher3)
24 # print cipher3
25 plain3 = ‘‘
26 for i in cipher3:
27     plain3 += chr(int(i, 16))
28 # print plain3
29 
30 #4. 第四层，根据plain3的形式（udd*），推测为unicode
31 cipher4 = plain3
32 cipher4 = re.findall(r‘u[\d\w]+‘, cipher4)
33 # print cipher4
34 cipher4 = ‘‘.join(cipher4).replace(‘u‘, ‘\u‘)
35 # print cipher4
36 plain4 = cipher4.decode(‘unicode-escape‘).encode(‘utf-8‘)#将unicode转中文，来自知乎
37 # print plain4    
38 
39 #5. 第5层，根据plain4形式，将所有数字转ASCII即可
40 cipher5 = plain4
41 cipher5 = re.findall(‘\d+‘, cipher5)
42 # print cipher5
43 plain5 = ‘‘
44 for i in cipher5:
45     plain5 += chr(int(i))
46 # print plain5
47 
48 #6. 第6层，百度plain5的编码格式(&#x)得到解码方法
49 cipher6 = plain5
50 # print cipher6
51 cipher6 = re.findall(r‘\d+\w?‘, cipher6)
52 # print cipher6
53 plain6 = ‘‘
54 for i in cipher6:
55     plain6 += chr(int(i, 16))
56 # print plain6
57 
58 #7. 第7层，百度plain6的编码格式（&#）得到解码方法
59 cipher7 = plain6
60 cipher7 = re.findall(‘\d+‘, cipher7)
61 # print cipher7
62 flag = ‘‘
63 for i in cipher7:
64     flag += unichr(int(i))
65 # print flag
66 flag = urllib.unquote(flag)
67 print flag