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Java program to swap two numbers with and without using third variable

//Java program to swap two numbers.
import java.util.*;

class SwapTwoNumbers
{
	public static void main(String []s)
	{
		int a,b;
		//Scanner class to read value
		Scanner sc=new Scanner(System.in);

		System.out.print("Enter value of a: ");
		a=sc.nextInt();
		System.out.print("Enter value of a: ");
		b=sc.nextInt();

		System.out.println("Before swapping - a: "+ a +", b: " + b);
		////using thrid variable
		int temp;
		temp=a;
		a=b;
		b=temp;
		//////////////////////
		System.out.println("After swapping  - a: "+ a +", b: " + b);
	}
}

import java.util.*;

class SwapTwoNumbers
{
	public static void main(String []s)
	{
		int a,b;
		//Scanner class to read value
		Scanner sc=new Scanner(System.in);

		System.out.print("Enter value of a: ");
		a=sc.nextInt();
		System.out.print("Enter value of a: ");
		b=sc.nextInt();

		System.out.println("Before swapping - a: "+ a +", b: " + b);
		////without using thrid variable
		a=a+b;
		b=a-b;
		a=a-b;
		//////////////////////
		System.out.println("After swapping  - a: "+ a +", b: " + b);
	}
}

Output

Enter value of a: 10
Enter value of a: 20
Before swapping - a: 10, b: 20
After swapping  - a: 20, b: 10

Enter value of a: 10
Enter value of a: 20
Before swapping - a: 10, b: 20
After swapping  - a: 20, b: 10