{}
alphabet=["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"]
password=[]
vary1,vary2=0,0
while True:
print("Do you want to (e)ncrypt or (d)ecrypt..")
decision=input(">")
data=input("please enter your message\n>").upper()
key=input("please enter your key\n>")
if decision=="e":
while vary1<len(data):
if data[vary1]==" ":
password.append(" ")
vary1+=1
r=alphabet.index(data[vary1])
r+=int(key)
if r>25:
t=r-26
password.append(alphabet[t])
else:
password.append(alphabet[r])
vary1+=1
elif decision=="d":
while vary2<len(data):
if data[vary2]==" ":
password.append(" ")
vary2+=1
r2=alphabet.index(data[vary2])
r2-=int(key)
password.append(alphabet[r2])
vary2+=1
else:
print("\nwrong input please try again")
continue
for repeator in range(0,len(password)):
print(password[repeator],end="")
password.clear()
play_again=(input("\ndo you want to continue yes or no\n>").upper())
if play_again=="NO":
print("\nThanks for creating passwords...")
break