#0250

Rotate Image Matrix

MediumDSA28 min20 XP

Problem

Given an n x n matrix, return a new matrix rotated 90 degrees clockwise.

Why This Matters

Matrix rotation combines coordinate thinking with a practical transform used in image and grid problems.

Function Signature

def rotate_matrix(matrix):

Examples

Example 1

Inputmatrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

Output[[7, 4, 1], [8, 5, 2], [9, 6, 3]]

The first row becomes the last column.

Constraints

Return the exact requested value.
Handle empty or small inputs when the prompt allows them.
Prefer the target DSA pattern over brute force when the input can grow.

CodePython

def rotate_matrix(matrix):
    """
    Input example: matrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
    Return: [[7, 4, 1], [8, 5, 2], [9, 6, 3]]
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return []

def rotate_matrix(matrix):
    """
    Input example: matrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
    Return: [[7, 4, 1], [8, 5, 2], [9, 6, 3]]
    Return the value from the function so the tests can compare it. Do not print unless the prompt asks.
    """
    # write your code here
    return []

Visible browser tests run here when available.

Testcases2 visible / 3 hidden categories

Three by three

Input[[1,2,3],[4,5,6],[7,8,9]]

Expected[[7,4,1],[8,5,2],[9,6,3]]

Every cell moves from (r, c) to (c, n - 1 - r).

One by one

Input[[5]]

Expected[[5]]

A single cell stays where it is.

Hidden Test Categories

two by two matrixnegative valueslarger square matrix