3.8.2 While loops

Basic Overview

Nesting is a term used when we use multiple loops inside of each other

Used when you want to you a loop multiple sets of times each set with different values

Many other versatile uses

Pseudocode Example

initialize outer_counter to 0
initialize inner_counter to 0

while outer_counter is less than 3:
    print "Apple"
    
    while inner_counter is less than 5:
        print "  Banana"
        increment inner_counter by 1
    
    reset inner_counter to 0
    increment outer_counter by 1

Python Example

outer_counter = 0
inner_counter = 0

while outer_counter < 3:
    print("Apple")
    
    inner_counter = 0
    while inner_counter < 5:
        print("  Banana")
        inner_counter += 1
    
    outer_counter += 1

Apple
  Banana
  Banana
  Banana
  Banana
  Banana
Apple
  Banana
  Banana
  Banana
  Banana
  Banana
Apple
  Banana
  Banana
  Banana
  Banana
  Banana

Javascript Example

%%js
let outerCounter = 0;
inner_counter = 0

while (outerCounter < 3) {
    console.log("Apple");

    innerCounter = 0;
    while (innerCounter < 5) {
        console.log("Banana");
        innerCounter++;
    }

    outerCounter++;
}

<IPython.core.display.Javascript object>

What is Happening

First, we initialize two different integers

Then we begin our first loop that will run until outerCounter greater than or equal to 3

Then we print out “Apple”

Then we set innerCounter to 0

Then we begin our second(nested) loop that will run until innterCounter is greater than or equal to 5

Then it prints out banana and increases the innercounter by one

Then in the first loop we increase outercounter by 1

this will lead to an output with 3 sets of

Apple Banana Banana Banana Banana Banana

Popcorn Hack #2

Create a piece of python code that prints out your name one time

then after printing your first name one time, print out your middle name 2 times

and finally print out your last name three times

this entire thing should be repeated 4 times

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