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Exercise 1: Drawing shapes

Adapt our simple code snippet to draw a triangle into a function that takes in a list of Point objects, a color name, and a GraphWin object and draws a triangle in the window. The function signature is given for you. Also, the “docstring” helps users of your function learn about what it does.

def drawTriangle(pointsList, colorName, win):
    """
    Draws a triangle in the given window.

    pointsList: the Point objects that give triangle bounds (a list)
    colorName: the color (a string)
    win: the window in which to draw (a GraphWin)
    """
    # TODO

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Exercise 2: The song of the animal kingdom

The animal kingdom is larger than just a farm. Your niece just got a new music animal toy for Christmas, and her poor parents have to hear it all the time. To torment your sibling further, you can write a program to display the song lyrics.

When switched to the non-farm side, the song might go like this:

Look, there's a parrot!
Look, there's a parrot!
Hey, ho, here we go,
look there's a parrot!
Squa-awk!

You should write a function that takes in an animal and its sound, and prints out the lyrics. Again, the function signature is given for you.

def printAnimalSong(animal, animalSound):
    """
    Prints a song about an animal.

    animal: the animal (a string)
    animalSound: the sound it makes (a string)
    """
    # TODO

Now, write a for loop in main that calls your function for each of these pairs:

• a monkey that says “oo-oo ah-ah”
• a lion that says “roar”
• a parrot that says “squa-awk”

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Exercise 3: Creating and drawing shapes

Modify your function from above to not only draw the triangle, but also return it. The updated signature and its docstring are given to you.

def drawTriangle(pointsList, colorName, win):
    """
    Draws a triangle in the given window.

    pointsList: the Point objects that give triangle bounds (a list)
    colorName: the color (a string)
    win: the window in which to draw (a GraphWin)

    returns: the created triangle object (a Polygon)
    """
    # TODO: copy your previous code, but now also return

Exercise 4: Writing functions that return values

Part a: Summing values

Write two functions:

• sumN(n) returns the sum of the first n natural numbers, i.e., 1+2+3+…+n
• sumNSquares(n) returns the sum of the squares of the first n natural numbers

Here are their signatures:

def sumN(n):
    """
    Computes the sum of the first n natural numbers.

    n: the number of ints to sum (an int)

    returns: the sum of numbers 1-n (an int)
    """
    # TODO

def sumNSquares(n):
    """
    Computes the sum of the squares of the first n natural numbers.

    n: the number of ints' squares to sum (an int)

    returns: the sum of the squares of 1-n (an int)
    """
    # TODO

Now, write a program that asks the user for a value of n, and uses these functions to print out the sum of the first n natural numbers and the sum of their squares.

def main():
    n = # TODO

    # TODO

Question: does the code still run even if you name your variable something else in main?

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