백준 2446 java

import java.util.Scanner;

public class bj2446 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int N;
        int i, j;

        N = scanner.nextInt();

        for(i = 0; i < N; i++)
        {
            for(j = 0; j < i; j++)
            {
                System.out.print(" ");
            }
            for(j = i; j < 2 * N - 1 - i; j++)
            {
                System.out.print("*");
            }
            System.out.println();
        }
        for(i = 1; i < N; i++)
        {
            for(j = 0; j < N - i - 1; j++)
            {
                System.out.print(" ");
            }
            for(j = 0; j < i * 2 + 1; j++)
            {
                System.out.print("*");
            }
            System.out.println();
        }

        scanner.close();
    }
}