Nested Loops

Nested loops extend the power of simple loops by allowing you to perform repeated actions across multiple dimensions. This is crucial for handling more complex tasks in a grocery store environment, such as organizing multi-layered inventory data or coordinating schedules across different departments.

Watch as Alex showcases how nested loops can be utilized to enhance efficiency and manage complex scenarios in our grocery store setting:

Nested loops are incredibly useful in programming when you need to loop through multiple sequences at the same time. By placing one loop inside another, you can iterate over elements in two or more dimensions, such as a list of lists:


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# List of lists representing stock in different departments
department_stocks = [
    ["Apples", "Bananas", "Cherries"],  # Fruits
    ["Milk", "Cheese", "Butter"],       # Dairy
    ["Bread", "Bagels", "Muffins"]      # Bakery
]

print("Inventory Check:")
for department in department_stocks:
    print(department) # For each iteration of the outer loop, the entire sublist is accessed
    # The inner loop then iterates over the items in that sublist
    for item in department:
        print(f" - {item}")
    print("")  # Add a line break for clarity

Notice how the outer loop iterates through each sublist in department_stocks, where each sublist represents a different department. The inner loop then iterates through all the items within each sublist. The outer loop does not proceed to the next sublist until the inner loop has finished iterating through all items in the current sublist.

Task

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Manage and display grocery store items from different aisles using lists and loops.

Combine the lists aisle1, aisle2, and aisle3 into a single list of lists called aisles.
Use a for loop to iterate through aisles using aisle as the loop variable.
For each aisle, print the aisle number starting from 1.
Use a nested for loop to iterate through the items in the current aisle using item as the loop variable.
Print each item in the specified format.

Output Requirements

Print aisle number as: Aisle: <aisle_number>
Print each item as: Contains <item>

Note

You can use the index() method to find the position of each aisle in the combined list.

Solution

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Section 5. Chapter 6

Nested Loops

Watch as Alex showcases how nested loops can be utilized to enhance efficiency and manage complex scenarios in our grocery store setting:


              1234567891011121314
            
# List of lists representing stock in different departments
department_stocks = [
    ["Apples", "Bananas", "Cherries"],  # Fruits
    ["Milk", "Cheese", "Butter"],       # Dairy
    ["Bread", "Bagels", "Muffins"]      # Bakery
]

print("Inventory Check:")
for department in department_stocks:
    print(department) # For each iteration of the outer loop, the entire sublist is accessed
    # The inner loop then iterates over the items in that sublist
    for item in department:
        print(f" - {item}")
    print("")  # Add a line break for clarity

Task

Swipe to start coding

Manage and display grocery store items from different aisles using lists and loops.

Combine the lists aisle1, aisle2, and aisle3 into a single list of lists called aisles.
Use a for loop to iterate through aisles using aisle as the loop variable.
For each aisle, print the aisle number starting from 1.
Use a nested for loop to iterate through the items in the current aisle using item as the loop variable.
Print each item in the specified format.

Output Requirements

Print aisle number as: Aisle: <aisle_number>
Print each item as: Contains <item>

Note

You can use the index() method to find the position of each aisle in the combined list.

Solution

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Thanks for your feedback!

Section 5. Chapter 6

Switch to desktop for real-world practiceContinue from where you are using one of the options below