Function checkKeys

ciphers/affine_cipher.py:24–32

(keyA, keyB, mode)

    return (keyA, keyB)

def checkKeys(keyA, keyB, mode):
    if keyA == 1 and mode == 'encrypt':
        sys.exit('The affine cipher becomes weak when key A is set to 1. Choose different key')
    if keyB == 0 and mode == 'encrypt':
        sys.exit('The affine cipher becomes weak when key A is set to 1. Choose different key')
    if keyA < 0 or keyB < 0 or keyB > len(SYMBOLS) - 1:
        sys.exit('Key A must be greater than 0 and key B must be between 0 and %s.' % (len(SYMBOLS) - 1))
    if cryptoMath.gcd(keyA, len(SYMBOLS)) != 1:
        sys.exit('Key A %s and the symbol set size %s are not relatively prime. Choose a different key.' % (keyA, len(SYMBOLS)))

def encryptMessage(key, message):
    ''&#x27;