# 15. Exercises¶

Write a program that prints

`We like Python's turtles!`

1000 times.Now, update that program to prompt the user for an integer and then print the same message the given number of times.

Write a program that prints out the lyrics to the song “99 Bottles of Beer on the Wall”

Write a program that prints even integers from 0 to 50.

- Write a program that uses a for loop to print
`One of the months of the year is January`

`One of the months of the year is February`

`One of the months of the year is March`

etc ...

Use

`for`

loops to make a turtle draw these regular polygons (regular means all sides the same lengths, all angles the same):- An equilateral triangle
- A square
- A hexagon (six sides)
- An octagon (eight sides)

# draw an equilateral triangle import turtle wn = turtle.Screen() norvig = turtle.Turtle() for i in range(3): norvig.forward(100) # the angle of each vertice of a regular polygon # is 360 divided by the number of sides norvig.left(360/3) wn.exitonclick()

# draw a square import turtle wn = turtle.Screen() kurzweil = turtle.Turtle() for i in range(4): kurzweil.forward(100) kurzweil.left(360/4) wn.exitonclick()

# draw a hexagon import turtle wn = turtle.Screen() dijkstra = turtle.Turtle() for i in range(6): dijkstra.forward(100) dijkstra.left(360/6) wn.exitonclick()

# draw an octogon import turtle wn = turtle.Screen() knuth = turtle.Turtle() for i in range(8): knuth.forward(75) knuth.left(360/8) wn.exitonclick()

Write a program that asks the user for the number of sides, the length of the side, the color, and the fill color of a regular polygon.

A drunk pirate makes a random turn and then takes 100 steps forward, makes another random turn, takes another 100 steps, turns another random amount, etc. A social science student records the angle of each turn before the next 100 steps are taken. Her experimental data is

`160, -43, 270, -97, -43, 200, -940, 17, -86`

. (Positive angles are counter-clockwise.) Use a turtle to draw the path taken by our drunk friend.On a piece of scratch paper, trace the the path of the turtle in the following program. When you are done, press

`run`

and check your answer.Write a program to draw a shape like this:

Write a program to draw a face of a clock that looks something like this:

Write a program to draw some kind of picture. Be creative and experiment with the turtle methods provided in Summary of Turtle Methods.

Create a turtle and assign it to a variable. When you print its type, what do you get?

A sprite is a simple spider shaped thing with n legs coming out from a center point. The angle between each leg is 360 / n degrees.

Write a program to draw a sprite where the number of legs is provided by the user.

Use a

`for`

statement to print 10 random numbers.Repeat the above exercise but this time print 10 random numbers between 25 and 35.

The

**Pythagorean Theorem**tells us that the length of the hypotenuse of a right triangle is related to the lengths of the other two sides. Look through the`math`

module and see if you can find a function that will compute this relationship for you. Once you find it, write a short program to try it out.Search on the internet for a way to calculate an approximation for

**pi**. There are many that use simple arithmetic. Write a program to compute the approximation and then print that value as well as the value of`math.pi`

from the math module.

## Weekly Graded Assignment¶

Assume you have a list of numbers `nums = [12, 10, 32, 3, 66, 17, 42, 99, 20]`

Write a loop that prints each of the numbers on a new line, like this:

12 10 ...etc

Write a second loop that prints each number and its square on a new line, precisely like this:

The square of 12 is 144 The square of 10 is 100 ...etc