Write a simple program to swap the numbers.

 Solution :- 

package mv;

public class SwapNumber {

public static void main(String[] args) {

int a=20;

int b=30;

System.out.println("Before swapping:a:"+a+",b:"+b);

int temp=a;

a=b;

b=temp;

System.out.println("After swapping: a:"+a+",b:"+b);

}

}