Java Program to add two binary numbers

Program

import java.util.Scanner;
public class AddTwoBinaryNumbers {
    public void addBinaryNumbers(long binaryNum1, long binaryNum2)
    {
        int i = 0;
        int  carry = 0;
        int[] sum = new int[20];
        while (binaryNum1 != 0 || binaryNum2 != 0) 
        {
          sum[i++] = (int)((binaryNum1 % 10 + binaryNum2 % 10 + carry) % 2);
          carry = (int)((binaryNum1 % 10 + binaryNum2 % 10 + carry) / 2);
          binaryNum1 = binaryNum1 / 10;
          binaryNum2 = binaryNum2 / 10;
        }
        if (carry != 0) {
        sum[i++] = carry;
        }
        --i;
        while (i >= 0) {
            System.out.print(sum[i--]);
        }
    }
    public static void main(String[] args)
    {
        AddTwoBinaryNumbers addTwoBinaryNumbers = new AddTwoBinaryNumbers();
        Scanner reader = new Scanner(System.in);
        System.out.print("Enter the first binary number: ");
        long binaryNum1 = reader.nextLong();
        System.out.print("Enter the second binary number: ");
        long binaryNum21 = reader.nextLong();
        System.out.println("Sum of two binary numbers is: ");
        addTwoBinaryNumbers.addBinaryNumbers(binaryNum1,binaryNum21);
    }
}

This program demonstrates adding two binary numbers without converting them into decimal.

Use Case:

This program is useful for understanding binary arithmetic and is suitable for scenarios where direct binary manipulation is required, such as in low-level programming or hardware design simulations.

1. Input:

   • The user is prompted to enter two binary numbers as long integers using the Scanner class.

2. Binary Addition:

   • Logic:
     • Binary addition follows these rules:
       • 0 + 0 = 0
       • 0 + 1 = 1
       • 1 + 1 = 10 (sum = 0, carry = 1)
       • 1 + 1 + carry = 11 (sum = 1, carry = 1)
   • The program performs digit-by-digit addition from right to left (least significant digit to most significant digit).
   • Each digit from both binary numbers is added along with any carry from the previous operation.

3. Implementation:

   • Variables:
     • i: Index for storing digits in the sum array.
     • carry: Tracks carry-over during addition.
     • sum[]: Array to store the result of binary addition in reverse order.
   • While Loop:
     • The loop runs until both binary numbers become 0.
     • % 10: Extracts the last digit of each binary number.
     • / 10: Removes the last digit of the binary number.
     • (binaryNum1 % 10 + binaryNum2 % 10 + carry) % 2: Computes the binary sum for the current position.
     • (binaryNum1 % 10 + binaryNum2 % 10 + carry) / 2: Updates the carry for the next iteration.
   • Handling Remaining Carry:
     • If there is a carry left after the loop, it is added to the sum array.

4. Output:

   • The sum array is printed in reverse order to display the final binary sum.

5. Execution:

   • Example:

     Enter the first binary number: 1101
     Enter the second binary number: 1011
     Sum of two binary numbers is:
     11000
     

   • Steps:
     • Add 1 + 1 = 10 (sum = 0, carry = 1)
     • Add 0 + 1 + carry = 10 (sum = 0, carry = 1)
     • Add 1 + 0 + carry = 10 (sum = 0, carry = 1)
     • Add 1 + carry = 10 (sum = 1, carry = 0)
     • Final result: 11000.

Key Features:

• Binary Arithmetic:
  • The program handles binary addition without converting to decimal, preserving efficiency for binary computations.
• Storage of Result:
  • The sum array stores digits in reverse order and is printed backward to ensure the correct order.

Output

$ javac AddTwoBinaryNumbers.java
$ java AddTwoBinaryNumbers
Enter the first binary number: 100101
Enter the second binary number: 101101
Sum of two binary numbers is:
1010010