Question

 class Ex1{
2.    public static void main(String args[]){
3.      int x = 10;
4.      int y = new Ex1().change(x);
5.      System.out.print(x+y);
6.    }
7.    int change(int x){
8.      x=12;
9.      return x;
10.   }
11. }

Can you please explain this entire code and what is happening?

Answer 1

Given code is
1. class Ex1{
2.    public static void main(String args[]){
3.      int x = 10;
4.      int y = new Ex1().change(x);
5.      System.out.print(x+y);
6.    }
7.    int change(int x){
8.      x=12;
9.      return x;
10.   }
11. }

This code initializes variable x with value 10.
Then calling function change with variable x.
change() function changing the value of x to 12 and returning updated x value.
As x is passed by value the value of x in main() function remains 10.
So, It returns 12.

Return value is getting stored in variable named y
So, the final values of x and y in main() method is 10 and 12 respectively.

Then main() prints the sum of x and y i.e 10+12 = 22
It prints 22.
Output is 22