WhaleCTF-德军密码（费纳姆密码）

二战时盟军截获德军一段密码，密文为：0000011000000000101010110111001011000101100000111001100100111100111001（密钥：helloworld），你可能会解出一个keyxxxxx的答案，请在y后面加{，结尾加}，答案的格式是key{xxxxx}，所以答案是?

不难看出是费纳姆密码，趁着练习这道题写了个脚本：

#费纳姆密码解密脚本
cipher = input("请输入密文：")
key = input("请输入密钥：")
miyao = ""
flag1 = ""
final = ""
for i in key:
    miyao += (str(bin(ord(i)))[2:])
for i in range(len(cipher)):
    flag1 += str(int(cipher[i])^int(miyao[i]))
#flag七个一组进行分割
step = 7
b = [flag1[i:i+step] for i in range(0,len(flag1),step)]
flag = []
for i in b:
	flag.append(i)
for i in flag:
    final += chr(int(i,2))
print("flag为："+final)

运行后得到flag