This is a simple Java program that swaps the values of two numbers using a temporary variable. Let me explain it line by line:

🔄 Swap Program Explanation 

public class Swap {

Defines a public class named Swap.

public static void main(String[] args) {

The main method where the program starts.

🧮 Variable Initialization 

int no1 = 10;
int no2 = 20;
  • no1 is assigned the value 10
  • no2 is assigned the value 20

🔁 Swapping Logic Using a Temp Variable 

int temp = no1;
  • Store the value of no1 (10) in a temporary variable temp. 
no1 = no2;
  • Now assign the value of no2 (20) to no1.
  • So, no1 becomes 20. 
no2 = temp;
  • Assign the value of temp (10) to no2.
  • So, no2 becomes 10.

🖨️ Output 

System.out.println(no1);
System.out.println(no2);

This will print:

20
10

✅ Values have been successfully swapped!

🔧 Bonus: Swap Without Temp Variable (Just for Fun) 

int a = 10, b = 20;
a = a + b;  // a = 30
b = a - b;  // b = 10
a = a - b;  // a = 20

Nice one, Sudhakar! This is a classic example of swapping two numbers without using a temporary variable. Let's break it down step by step:

🔁 Code Explanation: 

public class Swapwithout {

Defines a class called Swapwithout.

public static void main(String[] args) {

Program starts here.

🧮 Variable Initialization 

int no1 = 10;
int no2 = 20;
  • no1 is 10
  • no2 is 20

🧠 Swapping Logic (Without Temp Variable) 

no1 = no1 + no2;
  • no1 becomes 10 + 20 = 30 
no2 = no1 - no2;
  • no2 becomes 30 - 20 = 10 
no1 = no1 - no2;
  • no1 becomes 30 - 10 = 20

✅ Final Values

  • no1 = 20
  • no2 = 10 
System.out.println(no1); // prints 20
System.out.println(no2); // prints 10

💡 Output: 

20
10

📌 Summary:

You've swapped two numbers without using a third variable—just by using arithmetic. Great job!

Let me know if you want to try the same using bitwise XOR method too—it’s another cool trick!