Printing Asterisks Triangle Shapes in Java

Problem:

Write an application that displays the following patterns separately, one below the other. Use for loops to generate the patterns. All asterisks (*) should be printed by a single statement of the form System.out.print( '*' ); which causes the asterisks to print side by side. A statement of the form System.out.println(); can be used to move to the next line. A statement of the form System.out.print( ' ' ); can be used to display a space for the last two patterns. There should be no other output statements in the program. [Hint: The last two patterns require that each line begin with an appropriate number of blank spaces.]

                     

Shape (a):

public class Exercice2a

{
 public static void main (String[] args)
 {
  for (int count =0; count < 10; count++)
  {
    for (int j=0; j < count+1; j++)
       System.out.print("*");
    System.out.println();
  }
 }
}

Shape (b):

public class Exercice2b

{
 public static void main (String[] args)
 {
  for (int count =11; count >= 0; count--)
  {
    for (int j=0; j < count-1; j++)
       System.out.print("*");
    System.out.println();
  }
 }
}

Shape (c):

public class Exercice2c

{
 public static void main (String[] args)
 {
        for(int count = 0; count < 10; count++)
        {
            for(int index=1; index < count+1; index++)
                System.out.print(" ");

            for(int star=10; star > count; star--)
                System.out.print("*");
            System.out.println();
        } 
    }
}

Shape (d):

public class Exercice2d

 {
 public static void main (String[] args)
  {
        for(int count = 10; count > 0; count--)
        {
            for(int index=0; index < count-1; index++)
                System.out.print(" ");
            
            for(int star=10; star > count-1; star--)
                System.out.print("*");
            
            System.out.println();
        }
 }