Example: Number Diamond Pattern in Java

// Number Diamond Pattern
import java.util.Scanner;

// Main class containing the entry point of the program
public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // Step 1: Get user input for the number of rows
        System.out.print("Enter the number for the diamond (e.g., 4): ");
        int n = scanner.nextInt();

        // Step 2: Print the upper half of the diamond (including the middle row)
        for (int i = 1; i <= n; i++) {
            // Print leading spaces
            for (int j = 1; j <= n - i; j++) {
                System.out.print(" ");
            }
            // Print increasing numbers
            for (int j = 1; j <= i; j++) {
                System.out.print(j);
            }
            // Print decreasing numbers
            for (int j = i - 1; j >= 1; j--) {
                System.out.print(j);
            }
            System.out.println(); // Move to the next line
        }

        // Step 3: Print the lower half of the diamond
        for (int i = n - 1; i >= 1; i--) {
            // Print leading spaces
            for (int j = 1; j <= n - i; j++) {
                System.out.print(" ");
            }
            // Print increasing numbers
            for (int j = 1; j <= i; j++) {
                System.out.print(j);
            }
            // Print decreasing numbers
            for (int j = i - 1; j >= 1; j--) {
                System.out.print(j);
            }
            System.out.println(); // Move to the next line
        }

        scanner.close(); // Close the scanner
    }
}