Swap Two Numbers Without Using Third Variable In Java

Chapter: Miscellaneous Last Updated: 02-06-2023 05:21:11 UTC

Program:

            /* ............... START ............... */
                
public class NumberSwapper {
    public static void main(String[] args) {
        int a = 5;
        int b = 10;

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

        a = a + b;
        b = a - b;
        a = a - b;

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

                /* ............... END ............... */
        

Output

Before swapping:
a = 5
b = 10
After swapping:
a = 10
b = 5

Notes:

• In this code, the values of a and b are swapped without using a third variable. Here's how it works:
• Initially, a is assigned to a + b, which adds the values of a and b together.
• Then, b is assigned to the difference between a and b. At this point, b holds the original value of a.
• Finally, a is assigned to the difference between the updated value of a (previously a + b) and b. Now, a holds the original value of b. After these operations, the values of a and b have been swapped.

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