now let's tackle these now the two dues
are going to be as follows getting the
key from the user from the command line
getting the plaintext prompting for that
in ciphering that plaintext and then
finally printing the ciphertext back to
the user the key is going to be in the
command line argument and we can access
it as follows using the Arg V array in C
we simply called Arg V index 1 and in
Python we'll have to add in a system RV
for that then you'll also want to check
to make sure that your key is comprised
of all letters all alphabetic so use the
is alpha function here to check for that
to get the plain text from the user
prompt them for it using the getstring
function found in the cs50 module now
let's talk about in ciphering if I
wanted to iterate over all of the
letters in my name printing those then I
could store my name in a variable name
and then I would execute the for loop as
follows for C in name print C notice
here that the variable C is just a
placeholder the iterator for every
character in my name now if I ran this
then the print method would include a
new line after every character so make
sure to check up on how print works and
how to omit a new line coming
automatically after every call to print
alright so now that we know at the most
basic level how to iterate over a plain
text let's look at the formula for
visionnaire where we have the isolator
of the plain text shifted by the J
letter of the key and all of that is
modulo 2 by 26 and that gives you the
Ice letter of our cipher text so here
you'll notice that as before we have two
indices that we're dealing with I and J
but in the for loop example before we
only had the capability for one index or
one inner ATAR so you'll have to find a
way to keep track of your second index
now we want to advance that index in the
keyword only if the character in plain
text is a letter so go back to the is
alpha function and as before with our
ciphers we'll want to preserve the case
so you might want to use the is upper
and is lower functions finally you'll
want to implement alphabetical
wraparound I'll give you a hint to check
out these two functions and in
combination with the formula from before
figure out how to go back and forth
between ASCII values and alphabetical
indices to make sure that you wrap
around the alphabet correctly print the
ciphertext back to the user and you
finish the problem my name is zamyla and
this was vision f