Display the pattern like right triagle with a number program in java

Display the pattern like right  Triagle with a number program in java

1
12
123
1234
12345
123456
1234567
12345678
123456789
12345678910

12345678910
123456789
12345678
1234567
123456
12345
1234
123
12
1

10987654321
987654321
87654321
7654321
654321
54321
4321
321
21
1


for(a=12;a<1;a--)
for(b=12;b<a;b--)

System.out.println(b);

if (a==b){
System.out.println();
}




*
**
***

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