How to swap two numbers using only two variables in Java

 Here's a program to swap two numbers using only two variables with explanation using Java Programming language.

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import java.io.*;       class swap{        public static void main(String[]args) throws IOException{           int a,b;           DataInputStream din=new DataInputStream(System.in);             System.out.println("Enter the 1st no.(a): ");           a=Integer.parseInt(din.readLine());             System.out.println("Enter the 2nd no.(b): ");           b=Integer.parseInt(din.readLine());             a=a+b;           b=a-b;           a=a-b;             System.out.println("The swaping no. is " +a+ "," +b+".");        }     }

Output of Program:
 Enter the 1st no.(a): 5
 Enter the 2nd no.(b): 4

 The swaping no. is 4,5.