Concentric Square Pattern

Given an integer N, print a concentric square matrix of size (2*N - 1) x (2*N - 1) where the outermost border is filled with N, the next inner ring is N-1, down to 1 at the center.

Input Format

A single integer N.

Output Format

Print 2*N - 1 rows separated by space.

Constraints:1 <= N <= 9

Concepts Required:

Distance from 4 borders: min(i, j, size-1-i, size-1-j)Ring indexing: N - min_distance

Expected Pattern PreviewASCII Monospace

4 4 4 4 4 4 4
4 3 3 3 3 3 4
4 3 2 2 2 3 4
4 3 2 1 2 3 4
4 3 2 2 2 3 4
4 3 3 3 3 3 4
4 4 4 4 4 4 4

Notice how character spacing and row counts scale systematically based on the input N.

Concrete Examples

Example 1

Input:

Output:

4 4 4 4 4 4 4
4 3 3 3 3 3 4
4 3 2 2 2 3 4
4 3 2 1 2 3 4
4 3 2 2 2 3 4
4 3 3 3 3 3 4
4 4 4 4 4 4 4

Explanation: The matrix has size 7x7 with concentric rings decreasing from 4 down to 1.

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