#0217

Diagonal Matrix Pattern

MediumPython25 min20 XP

Problem

Return an n by n grid as a list of strings where both main diagonals are "*" and all other cells are ".".

Why This Matters

Matrix pattern questions build the exact row-column thinking needed for grids, images, and board problems.

Function Signature

def diagonal_pattern(n):

Examples

Example 1

Inputn = 5

Output["*...*", ".*.*.", "..*..", ".*.*.", "*...*"]

Cells on r == c or r + c == n - 1 become stars.

Constraints

Return the exact requested value.
Handle small edge cases cleanly.
Prefer readable Python over clever shortcuts.

CodePython

def diagonal_pattern(n):
    """
    Input example: n = 5
    Return: ["*...*", ".*.*.", "..*..", ".*.*.", "*...*"]
    For pattern problems, return a list of rows. Do not print the rows.
    """
    # write your code here
    return []

def diagonal_pattern(n):
    """
    Input example: n = 5
    Return: ["*...*", ".*.*.", "..*..", ".*.*.", "*...*"]
    For pattern problems, return a list of rows. Do not print the rows.
    """
    # write your code here
    return []

Visible browser tests run here when available.

Testcases1 visible / 3 hidden categories

Core example

Inputn = 5

Expected["*...*", ".*.*.", "..*..", ".*.*.", "*...*"]

Cells on r == c or r + c == n - 1 become stars.

Hidden Test Categories

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