Tuples

Tuples - immutable lists

Tuples

A tuple is a sequence of values, just like a list. The key difference is that tuples are immutable — once created, they cannot be changed. You cannot add, remove, or modify elements.

Creating a Tuple

Use parentheses instead of square brackets:

You can also create a tuple without parentheses — just commas are enough:

Python sees the comma and creates a tuple automatically. The parentheses are optional in most cases, but it's good practice to include them for clarity.

Single-element Tuple

This is a common gotcha — a single value in parentheses is not a tuple:

You must include a trailing comma to make a single-element tuple.

Indexing and Slicing

Tuples support the same indexing and slicing as lists:

Immutability

You cannot modify a tuple after creation:

This is the fundamental restriction. If you need to change values, use a list.

Tuple Unpacking

This is where tuples really shine. You can unpack a tuple into separate variables in one line:

This works with any number of elements:

You have already been using this without realizing it — whenever you write a, b = map(int, input().split()), map returns an iterable that gets unpacked into a and b.

Swapping Variables

Tuple unpacking makes swapping two variables a one-liner in Python — no temporary variable needed:

In C++ you need a temporary variable for this. In Python, the right side is evaluated as a tuple first, then unpacked.

What You Can Do with Tuples

Tuples support all read operations that lists support:

When to Use Tuples vs Lists

Use a list when your collection may change — you plan to append, remove, or modify elements.

Use a tuple when your collection is fixed — coordinates, RGB values, a pair of values you want to unpack, or a key in a dictionary.

In competitive programming tuples come up most often in two situations: unpacking multiple return values from a function, and as keys in dictionaries.