How to generate a CIRCULAR MATRIX using Multi-Dimensional Arrays

I have been asked to write a program for circular matrix in a interview programming round. 

Following program is a generic way of creating a circular matrix:

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package blogspot.thinkwithjava; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; /** * * @author R.D * */ class CircularMatrix { public static void main(String args[]) throws IOException { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); System.out.print("Enter the number of elements : "); int n = Integer.parseInt(br.readLine()); int A[][] = new int[n][n]; int k = 1, c1 = 0, c2 = n - 1, r1 = 0, r2 = n - 1; while (k <= n * n) { for (int i = c1; i <= c2; i++) { A[r1][i] = k++; } for (int j = r1 + 1; j <= r2; j++) { A[j][c2] = k++; } for (int i = c2 - 1; i >= c1; i--) { A[r2][i] = k++; } for (int j = r2 - 1; j >= r1 + 1; j--) { A[j][c1] = k++; } c1++; c2--; r1++; r2--; } /* Printing the Circular Matrix */ System.out.println("The Circular Matrix is:"); for (int i = 0; i < n; i++) { for (int j = 0; j < n; j++) { System.out.print(A[i][j] + "\t"); } System.out.println(); } } }

The output will look like this: