C++ Tutorial: Caesar cipher | encryption and decryption (Very easy)

Hey!
Hope you will like this short tutorial. :)

Programs used:

IDE: http://www.eclipse.org/downloads/eclipse-packages/
Compiler: http://www.mingw.org/

Let's start!

We are looking for an encryption like this:
https://i.imgur.com/h3RIx7k.jpg

Therefore we need nothing special.
Only 3 variables.
https://i.imgur.com/8ZphUmi.png

We can also write the code to input our variables.
https://i.imgur.com/EruUOiE.png

Now we need a for-loop to go through every letter.
Therefore we declared the variable " inputLength " wich gives us the length of our input with:
https://i.imgur.com/FfHm54o.png
In our for-loop we are checking if the current charactere is alphanumeric.
https://i.imgur.com/2E1pkni.png
Now we are converting our upper case letters into lower case letters.
https://i.imgur.com/oLCtLHd.png

In our loop we need another for-loop wich is our displacement.
Inside there we check if the current letter is " z " and if it's true, then convert it to " a ".
That's because we don't want to run out of letters if we reach " z ".

We also add an else statement. In there we are just counting up our input variable.
https://i.imgur.com/d7PtTFj.png

For the decrypting we are doing almost the same, but instead of counting our input variable up, we are counting it down.
https://i.imgur.com/xjGkPbY.png

That's it! Hope you like it :)