How do i force my code to print in python

问题

I'm having trouble trying to work out an error in my code. It isn't printing the final product and leaving a blank space.

playing = True
string = ""
Alphabet = ('z','a','b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z')

while playing == True:
    string = ""
    eord = input('Type "d" to "decrypt" and "e" to "encrypt": ')

    if eord == 'e':
        texte = input ("Type your word to encrypt: ")
        key1 = int(input("Choose a key between 1-26: "))
        for letter in texte:
            number = (ord(letter)) + (key1)
            letter=(chr(number))
            string = (str(string)) + (str(letter))
        print (string)
        keyword = input ("Type 'encrypt' code further or 'decrypt' further: ")

        if keyword == 'encrypt':
            plainText = input("Please enter the plain text: ")
            key = input("Please enter the key: ")
            keyList = []
            keyLength = 0
            while keyLength < len(plainText):
                for char in key:
                     if keyLength < len(plainText):
                         keyList.append(str(char))
                         keyLength = keyLength + 1
                         CipherText = [] 
                         IndexValue = 0
                         keyIncrement = 0
                     for plainTextChar in plainText:
                         IndexValue = Alphabet.index(keyList[keyIncrement]) + Alphabet.index(plainTextChar)
                         while IndexValue > 26:
                             IndexValue = IndexValue - 26
                             CipherText.append(Alphabet[IndexValue])
                             keyIncrement = keyIncrement + 1
                         print (''.join(CipherText))
                         import sys
                         sys.stdout.flush()

                         finish = input('Would you like to go again Y or N')
                         if finish == 'n' or 'N':
                             retry = input ("Would you like to go again? Y or N: ")
                             if retry == 'N' or 'n':
                                 print ("Please exit the window")
                                 import sys
                                 sys.exit()

    elif eord == 'd':
        texd = input ("Type your word to decrypt: ")
        key2 = int(input("Choose a key between 1-16: "))

        for letter in texd:
            number = (ord(letter)) - (key2)
            letter=(chr(number))
            string = (str(string)) + (str(letter))
        print (string)
        keyword = input ("Type 'encrypt' code further or 'decrypt' further: ")

        if keyword == 'decrypt':
             plainText = input("Please enter the plain text: ")
             key = input("Please enter the key: ")
             keyList = []
             keyLength = 0
             while keyLength < len(plainText):
                 for char in key:
                     if keyLength < len(plainText):
                         keyList.append(str(char))
                         keyLength = keyLength - 1
                         completeCipherText = [] 
                         cipherCharIndexValue = 0
                         keyIncrement = 0
                     for plainTextChar in plainText:
                         cipherCharIndexValue = Alphabet.index(keyList[keyIncrement]) + Alphabet.index(plainTextChar)
                         while cipherCharIndexValue > 26:
                             cipherCharIndexValue = cipherCharIndexValue + 26
                             completeCipherText.append(Alphabet[cipherCharIndexValue])
                             keyIncrement = keyIncrement - 1
                         print (''.join(completeCipherText))

                         finish = input('Would you like to go again Y or N')
                         if finish == 'n' or 'N':
                             retry = input ("Would you like to go again? Y or N: ")
                             if retry == 'N' or 'n':
                                 print ("Please exit the window")
                                 import sys
                                 sys.exit()

Is there a way i can fix this or force it to print?

Here is the output of the code.

Type "d" to "decrypt" and "e" to "encrypt": e
Type your word to encrypt: hello
Choose a key between 1-26: 3
khoor
Type 'encrypt' code further or 'decrypt' further: encrypt
Please enter the plain text: python
Please enter the key: cipher

Would you like to go again Y or N

回答1:

You have the problem with tab spacing. Concretely here:

                     while IndexValue > 26:
                         IndexValue = IndexValue - 26
                         CipherText.append(Alphabet[IndexValue])
                         keyIncrement = keyIncrement + 1

For the first pass the IndexValue is 19, so it skips also CipherText append. And therefore there is nothing to print out.

Correct indentation here:

                     while IndexValue > 26:
                         IndexValue = IndexValue - 26
                     CipherText.append(Alphabet[IndexValue])
                     keyIncrement = keyIncrement + 1

Then again you are asking whether to finish when still in the encrypting for loop.

However you have other flaws in your design. If the key is longer than 1 char you end up in Index error due to the keyList having just just 1 item. While you expect more items in keyList in the for loop.

来源：https://stackoverflow.com/questions/34246133/how-do-i-force-my-code-to-print-in-python