Why is error generating in this code?

Question

class mo {
public static void main(String ab[])
{
int a=Integer.parseInt(ab[0]);
int b=Integer.parseInt(ab[1]);
int c=a+b;
System.out.println(c);
}
}

Answer 1

if you run this program in ide you don't have any parameters in main class and there is no 0 or 1 element

Answer 2

and you need one more }

Answer 3

Yup one more}

Answer 4

But this code is running properly in other systems

Answer 5

you need to start this code on command line as follows

java po 20 12

Answer 6

Thanks