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HSSP Introductory Python Programming through Games

This is a repository that holds the code for the Summer 2018 intro to python programming for MIT's HSSP program.

This code was developed for Python (version 2.7).

Running the game templates and game example relies on the Pygame library (version 1.9.3) which can be downloaded here.

If you are looking to program without having to install Python on your computer, we recommend using the www.learnpython.org which is an interactive tutorial that covers many of the same topics as we will in the course.

Instructions for July 14th class (If/Else statements)

Using the green button, download the code to your computer. Extract the folder saying yes to all the prompts. Inside the extracted HSSP_Python-master folder, drag the lesson 2 folder to the desktop.

Find your terminal. It should already be up as a black screen on your computer, if it's not use the search feature to open it.

Now type into the terminal:

cd ~/Desktop/lesson2

Remember that computers are picky, so all the characters should be the exact case and spacing. Now we can run the code from inside the folder, type into the terminal:

python text_adventure_game.py

Enter commands at the appropriate prompts. What happens if you don't follow the instructions? Try typing "yes" instead of "y".

Now we can take a look at the code. Type once again into the terminal

gvim text_adventure_game.py

Now we can see there is an if statement based on the variable go_in which stores the users' response to opening the gate. What are the potential user responses? How does the computer respond?

If the user responds with a "n" to opening the gate, there is a second question and responses. What are the potential user responses? How does the computer respond?

elif go_in == "n":
    direction = raw_input("You decide to go home, but you've forgotten the way! Do you go left, right, or straight? (left,right,straight) ")
    if direction == "left":
        # enter your code here to continue the story
        print("What happens? You decide...")
    elif direction == "right":
        # enter your code here to continue the story
        print("What happens? You decide...")
    elif direction == "straight":
        # enter your code here to continue the story
        print("What happens? You decide...")
    else:
        print("Invalid input! You can't play :p")

We can tell the question about which way to turn only happens if the variable go_in is "n" because everything under it is indented. Indenting improperly can cause errors in the code. We can see here we test three directions. First fill in new responses by modifying the code for each direction. Test your new responses by running the code:

python text_adventure_game.py

You may have noticed if you decide to open the gate and you get a choice to pick the lock, but nothing happens! This is the section of code:

if go_in == "y":
    print("You yank on the gate, but the large gold lock won't budge.")
    pick_lock = raw_input("Do you try to pick the lock? (y or n) ")
    # enter your if statement here to decide what happens if you try to pick the lock
    print("What happens? You decide...")

Try replacing the print statement by writing your own if statement. Remember that we will be comparing the variable pick_lock which holds the string input from the user to look for our two outcomes ("y" or "n"). Try adding a third outcome if the user enters a bad input as an else statement, this will catch any input that isn't "y" or "n".