def encrypt_vigenere(plaintext:str,keyword:str) -> str:
     a = ('abcdefghijklmnopqrstuvwxyz')
     ciphertext=str()
     s = 0
     for i in plaintext:
         if i != (' '):
            ciphertext += str(a[(a.index(i)+a.index(keyword[s%len(keyword)]))%26])
         else:
             ciphertext+=(' ')
         s += 1
     print(ciphertext)
     return(ciphertext)
def decrypt_vigenere(ciphertext:str,keyword:str) -> str:
     a = ('abcdefghijklmnopqrstuvwxyz')
     plaintex=str()
     s = 0
     for i in ciphertext:
         if i != (' '):
            plaintex += str(a[(a.index(i)-a.index(keyword[s%len(keyword)]))%26])
         else:
             plaintex+=(' ')
         s += 1
     print(plaintex)
     return(plaintex)
x = input('Enter text: ')
y = input('Enter keyword: ')
g = input('Do you want do encrypt this text?(yes/no):')
if g == ('yes'):
    encrypt_vigenere (x,y)
elif g ==('no'):
    decrypt_vigenere(x,y)
else:
    print('incorret input')