"Python Essentials" is a comprehensive course designed for college preparation, offering an engaging and practical introduction to Python programming. This course covers fundamental topics such as variables, data types, string operations, conditionals, loops, and more. With a focus on real-world applications, learners will develop a solid foundation in Python, preparing them for further studies or a career in programming.

Print to console

Console output

Brave new world

Variables introduction

Data Types in Python

A warm welcome

String interpolation

Python naming convention

The resistance base

Comments in Python

Python problems practice

The mission

If statement

Bool type introduction

Back to the streets

Reading From Console in Python

Nested conditionals

Who is your friend?

Introduction to for loop

Introduction to a float type

The basement

Introduction to while loop

Introduction to functions

Reparing Noname

Introduction to lists

Lists - advanced operations

Victory is close

Modules

Modulo operation

Python test

Wonderland

Python Essentials

A college preparation python course.

Now that I had the code for the basement, I just needed to find the basement and figure out how to 

 the code. In all my time at the base I had never heard anything about a secret storage area, so I knew I had some sleuthing to do. I figured I'd start by taking the elevator to the lowest floor it accessed and then searching for some sort of inconspicuous back stairwell that would lead me even deeper.

I walked calmly to the elevator, pressed the down button, and was relieved to see that I was the only one in the hallway. When the doors opened, my luck continued and I got on for a solo ride down. I looked over to the button panel and, to my surprise, there was an actual Basement button. Maybe I wouldn't have to sneak around to find the entrance after all!

After about 30 seconds, the elevator stopped one floor 

 the basement. I should have known that it couldn't be as easy as pressing a single button. The number on the screen above the door disappeared and a message appeared: "Only base leaders can access the basement. You will be given programming assignments on advanced topics, including console input and nested conditionals. Fail the task, and lasers will split you into atoms. Have a nice day!"

This language of the future "do this or we kill you" started to wear off on me. At least it is direct! Having second thoughts about taking the test right now, I frantically punched the numbers on the button panel, willing the elevator to realize that I would prefer to be anywhere but there at the moment. Thankfully, it registered before the quiz could start, and the elevator just happened to deliver me to the floor that I lived on. 

I know console input but "nested conditionals" is a new topic for me. Back in my room, I entered a local wiki. It had a page entitled "Nested conditionals".

Nested conditionals are conditional statements placed within other conditional statements. You might need to use them if the logic of your program is a bit more complicated than a simple if/else. They look like this:

These structures can get deep and complicated, as 

you can nest a new conditional in any branch of an existing one.

Consider a programming task: given 3 numbers, find a middle one by value. When the user inputs 3 arbitrary integers - 

, they can be arranged by value in any of these 6 situations:

First, let's solve a simpler task, and just determine if a is smaller than b or not.

, it means we are in a situation 1, 2, or 5 (a b c; a c b; c a b). To determine the exact order we would need to write more if statements and place them inside the previously written one:

Try to implement the else branch for this assignment yourself, so that the resulting code finds the middle number.

Now, that you know one way of finding a middle number, we can improve on it, to make it closer to how experienced programmers will write it.

! You can compare the numbers one by one, using <, >, ==, and other comparison operations. For example, here is how you can check that b lies between a and c:

And the last improvement: if you want to nest if directly inside the '

' statement, you can use the 'elif' instead:

elif makes the code shorter, but still easy to read. We recommend using it!

Now rewrite your previous solution to use chained comparisons.

I read and re-read the terminology until I felt I could recite it by heart. After another shot of weak coffee to boost my courage, I headed back to the elevator and hit that Basement button again. Yep, still a terrifying threat of death by laser. I was fairly confident this time around though, and I managed to stand still as a big laser cannon appeared from the ceiling and angled itself toward me. A small touch screen popped out of the panel opposite the buttons and gave me the following tasks:

The laser cannon retracted back into the ceiling panel. Wow! It wasn't so hard! The doors slid open and I walked down a short corridor and began descending a flight of stairs. This must lead me to where I can input the secret code! 
Suddenly, the stairs began spinning. Faster and faster.

I was trying to figure out if it was real or not when an electronic voice broke my concentration. 
"To stop spinning, prove that you have the secret knowledge."

I did it, I solved all the tasks! The world finally stopped spinning and whatever had just happened deposited me at the bottom of the stairs, facing a wall. An old 10-digit keypad was mounted there, and I entered the secret code, 145. There was a grinding noise, and the whole wall rotated revealing what was hiding in the basement all this time.

Learn to create complex logical flows using nested conditionals in Python. This lesson on CodeEasy.io takes you through examples and best practices for deeper control structures in programming.