my_alp = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
def rotate(x , y):
    z = my_alp.find(x)
    if ((z + y) > 25):
        w = (z + y) % 26
        return my_alp(w)
    return my_alp(z + y)
def cencrypt(x , y):
    x = x.upper()
    if len(x) == 1:
        return rotate(x , y)
def c_encrypt(x , y):
    x = x.upper()
    c= cencrypt(x , y)
    return c
def cdecrypt(string , key):
    string = string.upper()
    if len(string) == 1:
        return rotate(string , key * -1)
def c_decrypt(string , key):
    string = string.upper()
    new_string = cdecrypt(string , key * -1)
    return new_string
def vig_rotate(x , y):
    first_index = my_alp.find(x.upper())
    last_index = (first_index +y) % 26
    return(my_alp(last_index))
def vig_encrypt(x , y):
    encryption = ''
    for character in x:
        if character.isalpha():
            encryption += vig_rotate(character , y)
        else:
            encryption += character
    return(encryption)
def vig_decrypt(x , y):
    encryption = ''
    for character in x:
        if character.isalpha():
            encryption += vig_rotate(character , y * -1)
        else:
            encryption += character
    return encryption