CodeBhavya

PYTHON PROGRAM • LISTS

Append and Extend a List in Python

Learn append and extend a list in python with a short, executable Python example.

Beginnerappend()extend()

PROBLEM UNDERSTANDING

Input and expected output

Sample input
No input required
Sample output
[1, 2, 3, 4, 5]

COMPLETE PYTHON PROGRAM

Complete Python implementation

python-list-append-extend.py
Open in compiler
values = [1, 2]
values.append(3)
values.extend([4, 5])
print(values)

GUIDED CODE TOUR • NOT LIVE EXECUTION

Study the program line by line

Use the real compiler button above to run and debug with different inputs.

CURRENT STEP

Select Start to walk through the important lines.

SELECTED LINE

No line selected

EXPECTED OUTPUT FOR THE SAMPLE

[1, 2, 3, 4, 5]
0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

  1. Initialize the sample values used to append and extend a list.
  2. Apply append() and extend() to compute the required result.
  3. Display the result for append and extend a list and compare it with the documented sample output.

This example of append and extend a list computes the result directly from the prepared sample data. It demonstrates append() and extend() and prints a deterministic result that can be checked against the sample output.

EFFICIENCY

Time and space complexity

Time complexity

O(1)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

Check this

For append and extend a list, keep the data shape and value types consistent with append().

Check this

Apply append() in the same order shown by the algorithm; changing the order can change the result.

Check this

Verify the final append() and extend() result against the sample before trying new data.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.