Spiral Hybrid with Diagonal Numbers

This program prints a spiral of stars with numbers on diagonals.

Problem Statement

Write a Java program that prints a 7x7 spiral of stars with numbers placed on diagonals.

Source Code

1 public class SpiralHybridDiagonalNumbers {
2 public static void main(String[] args) {
3 int n = 7;
4 char[][] arr = new char[n][n];
5 int top=0, left=0, bottom=n-1, right=n-1;
6 while(top<=bottom && left<=right) {
7 for(int i=left; i<=right; i++) arr[top][i]='*';
8 top++;
9 for(int i=top; i<=bottom; i++) arr[i][right]='*';
10 right--;
11 for(int i=right; i>=left; i--) arr[bottom][i]='*';
12 bottom--;
13 for(int i=bottom; i>=top; i--) arr[i][left]='*';
14 left++;
15 }
16 for(int i=0; i<n; i++) {
17 for(int j=0; j<n; j++) {
18 if(i==j || i+j==n-1) System.out.print(i+1 + " ");
19 else System.out.print(arr[i][j] + " ");
20 }
21 System.out.println();
22 }
23 }
24 }

Program Output

1 * * * * * 7 
* 2 * * * 6 * 
* * 3 * 5 * * 
* * * 4 * * * 
* * 5 * 3 * * 
* 6 * * * 2 * 
7 * * * * * 1 

Explanation

The spiral outline is filled with stars, and the diagonal condition then overlays the row index at diagonal cells, combining the spiral star outline with a numeric diagonal cross.

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