Caesar cipher python错误

Question

我刚接触密码学，所以我试着用python做一个简单的Caesar密码程序，但它总是只返回一个字母。有谁能帮帮忙吗？下面是我的代码：

def main():

    text = raw_input('input plainteks:')
    key  = int(raw_input('input key:'))

    print("plain teks :"+text)
    print("key :" +str(key))
    print("hasil cipher:", encrypt(text,key))

def encrypt(text,key):

    hasil = ''

    for i in range(len(text)): #
        char = text[i]

    if (char.isupper()):
        hasil += chr((ord(char) + key-65)%26 + 65)
    else:
        hasil += chr((ord(char) + key-97)%26 + 97)
    return hasil

下面是我尝试运行它的时候：

input plainteks:melody  
input key:3 
plain teks :melody
key :3
hasil cipher: b

Answer 1

您的if不在循环中。下面的代码可以工作：

def main():

    text = raw_input('input plainteks:')
    key  = int(raw_input('input key:'))

    print("plain teks: "+text)
    print("key: " +str(key))
    print("hasil cipher: "+encrypt(text,key))

def encrypt(text,key):
    hasil = ''
    for i in range(len(text)): #
        char = text[i]
        if (char.isupper()):
            hasil += chr((ord(char) + key-65)%26 + 65)
        else:
            hasil += chr((ord(char) + key-97)%26 + 97)
    return hasil

main()

您还可以使用secretpy模块

from secretpy import Caesar

text = 'melody'
key = 3
print(text)
cipher = Caesar()
enc = cipher.encrypt(text, key)
print(enc)