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    Lab 12: Part 1: Non-fruitful Recursion 
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# Lab 12: Part 1: Non-fruitful Recursion
Create a new file called `lab12.py`. All the functions you write today will be **recursive**, and in this section, **non-fruitful**. Your functions will print, but not return values. Later on today, you'll move on to **fruitful** recursive functions.


## Task 0. divideBy3

<div class='partnerA'>Partner A</div>

Write a function called `divideBy3` that will take a number and
divide the number by 3, printing the number unless it is less than or equal to 1.
**This function must be recursive**.
```py
>>> divideBy3(3)
  3


>>> divideBy3(1)


>>> divideBy3(0)


>>> divideBy3(-4)


>>> divideBy3(15)
  15
  5.0
  1.6666666666666667

>>> divideBy3(100)
  100
  33.333333333333336
  11.111111111111112
  3.703703703703704
  1.234567901234568
```


## Task 1. Recursive triangles

<div class='partnerB'>Partner B</div>

In this task, you will create some recursive patterns using asterisks.

Write a Python function called `asteriskTriangle` that will take a `length` parameter and draw a triangle pattern composed of lines of asterisks that get successively smaller with each line.

**This function must be recursive**.
<br><br>
Example invocations of `asteriskTriangle`:
<br>
<!--img src="atri.png" style="max-width: 600px"-->
```py
>>> asteriskTriangle(1)
  *

>>> asteriskTriangle(3)
  ***
  **
  *

>>> asteriskTriangle(5)
  *****
  ****
  ***
  **
  *

>>> asteriskTriangle(15)
  ***************
  **************
  *************
  ************
  ***********
  **********
  *********
  ********
  *******
  ******
  *****
  ****
  ***
  **
  *

>>> asteriskTriangle(0)

>>>
```

## Task 2. switch

<div class='partnerB'>Partner B</div>

Write a function called `switch` that will take a length parameter and draw a  pattern like the examples below. The examples below always use asterisks and dashes:`*` and `-`. You can change those if you like, or, even better, add parameters so the user can specify their own symbols. **This function must be recursive**.
```py
>>> switch(0)


>>> switch(1)

>>> switch (2)
  **

>>> switch(3)
  ***---
  **
  ---***

>>> switch(6)
  ******------
  *****-----
  ****----
  ***---
  **
  ---***
  ----****
  -----*****
  ------******

>>> switch(8)
  ********--------
  *******-------
  ******------
  *****-----
  ****----
  ***---
  **
  ---***
  ----****
  -----*****
  ------******
  -------*******
  --------********
```


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