问题
I am currently trying to write a program, for school, in order to encrypt and decrypt a inputted message. I need the encrypted or decrypted message to only be in the alphabet no other symbols or keys, for example, with an inputted offset of 5 using the message van to encrypt, i want it to output 'afs'. Can anyone help please? This is my code currently.
def find_offset():
offset = int(input("Enter an offset: "))
if offset > 25 or offset < 0:
print("Invalid offset, please enter another offset: ")
find_offset()
else:
print("Okay")
encrypt_fun(offset)
def encrypt_fun(offset):
choice = ''
while choice != '3':
choice = input("\nDo you want to encrypt or decrypt the message?\nEnter 1 to Encrypt, 2 to Decrypt, 3 to Exit Program: ")
if choice == '1':
message = input("\nEnter the message to encrypt: ")
for i in range(0, len(message)):
result = chr(ord(message[i]) + offset)
print(result, end=''),
elif choice == '2':
message = input("\nEnter the message to decrypt: ")
for i in range(0, len(message)):
result = chr(ord(message[i]) - offset)
print(result, end=''),
elif choice != '3':
print("You have entered an invalid choice. Please try again.\n\n")
find_offset()
回答1:
def getOffset():
offset = -1
while not 0 < offset < 25:
try: offset = int(input("Please enter an integer offset between 1 and 25: "))
except ValueError: continue
return offset
def encrypt(msg, offset):
base = ord('a')
chars = (ord(char)-base for char in msg)
cipher = (base + ((c+offset)%26) for c in chars)
return ''.join([chr(c) for c in cipher])
decrypt = lambda msg,offset: encrypt(msg, -offset)
def main():
msg = """Please choose
[1] to encrypt
[2] to decrypt
[3] to exit
"""
funcs = {1: encrypt, 2: decrypt}
while True:
try: choice = int(input(msg))
except ValueError: continue
if choice == 3: return
message = input("Please enter the message that you would like to {}: ".format(funcs[choice].__name__))
offset = int(input("Please enter the offset: "))
print(funcs[choice](message, offset))
来源:https://stackoverflow.com/questions/35564347/encryption-and-decryption-within-the-alphabet-python-gcse