Right rotation
Input
rotate_list([1, 2, 3, 4, 5], 2)
Output
[4, 5, 1, 2, 3]
Each element moves two positions to the right; the last two wrap to the front.
Full lesson preview
Rotate List by N Positions
Rotate a list by n positions. Positive n rotates to the right, negative n rotates to the left.
Python practice15 minLoops & IterationIntermediateLast updated March 15, 2026
Problem statement
Implement rotate_list(lst, n) that returns a new list which is the input list rotated by n positions. A positive n means rotate to the right; a negative n means rotate to the left. Rotation should wrap around and handle |n| larger than the list length. The original list must not be mutated.
Task
Practice index arithmetic, modular arithmetic, and handling edge cases like empty lists or n larger than list length.
Examples
Input format
Two arguments: lst (a list) and n (an integer).
Output format
A new list rotated by n positions.
Constraints
Do not use external libraries. Aim for O(n) time and O(n) extra space for the returned list. The input list may be empty.
Samples
Sample 1
Input
rotate_list([1, 2, 3], -1)
Output
[2, 3, 1]
Negative n rotates left by 1.