YildizlarlaElmas.java

import java.util.Scanner;

public class YildizlarlaElmas {
    public static void main(String[] args) {
         int n,a,b,c;
         Scanner inp = new Scanner(System.in);

        System.out.print("bir sayı giriniz: ");
        n = inp.nextInt();

        for(a=1; a<=n; a++){
            for(b=1; b<=(n-a); b++){
                System.out.print(" ");
            }
            for(c=1; c<=(2*a-1); c++){
                System.out.print("*");
            }
            System.out.println(" ");
        }

        for(a=1; a<n; a++){
            for(b=1;b<=a; b++){
                System.out.print(" ");
            }
            for(c=1; c<=(2*n-(2*a+1)); c++){
                System.out.print("*");
            }
            System.out.println(" ");
        }

    }
}