Empat Segitiga Siku-Siku

//PATRICIA DIANITA WIJAYA
import java.util.Scanner;

public class SegitigaBintang
{
//patriciadianitawijaya.blogspot.com

    public static void main (String [] args) 
    {
    System.out.print("PROGRAM 4 BENTUK SEGITIGA BINTANG");
    Scanner input = new Scanner ( System.in );
    System.out.print("Pilih segitiga (1,2,3,4) = ");
    int x = input.nextInt();
    SegitigaSikuBintang1 baru = new SegitigaSikuBintang1();
           switch ( x )
    {
    case 1: baru.Segitia_a();
    break;
  
    case 2: baru.Segitia_b();
    break;
   
    case 3: baru.Segitia_c();
    break;
   
    case 4: baru.Segitia_d();
    break;     }
    }   
}

-----------------------------------------------------------------

import java.util.Scanner;

public class SegitigaSikuBintang1 {
public void Segitia_a()
{

int batas, a,b;
Scanner input = new Scanner (System.in);
System.out.print("Masukkan batas = ");
batas = input.nextInt();

for ( a = 0 ; a <= batas ; a++)
{
for (b = 0 ; b < a ; b++)
{
System.out.print("*");
}
System.out.print("\n");
}


}
public void Segitia_b()
{

int batas, a,b;
Scanner input = new Scanner (System.in);
System.out.print("Masukkan batas = ");
batas = input.nextInt();

for ( a = batas ; a >= 0 ; a--)
{
for (b = 0 ; b < a ; b++)
{
System.out.print("*");
}
System.out.print("\n");
}


}

public void Segitia_c()
{

int batas, a,b,c;
Scanner input = new Scanner (System.in);
System.out.print("Masukkan batas = ");
batas = input.nextInt();

for(a=batas;a>0;a--)
{
for(b=a-1;b>0;b--)
{
System.out.print(" ");
}
for(c=batas-(a-1);c>0;c--)
{
System.out.print("*");
}
System.out.print("\n");
}

}

public void Segitia_d()
{

int batas, a,b,c;
Scanner input = new Scanner (System.in);
System.out.print("Masukkan batas = ");
batas = input.nextInt();

for(a=1;a<=batas;a++)
{
for(b=0;b<a;b++)
{
System.out.print(" ");
}
for(c=0;c<batas-(a-1);c++)
{
System.out.print("*");
}
System.out.print("\n");
}



}
}

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