Add Two Binary Strings in Java

In this article, we will understand how to add two binary strings in Java. A binary string is a sequence of numbers represented in bytes 0s and 1s.

Below is a demonstration of the same −

Input

Suppose our input is −

10101
10001

Output

The desired output would be −

100110

Algorithm

Step 1- START
Step 2- Create new scanner object
Step 3- Enter two binary inputs
Step 4- Define a carry flag
Step 5- Use while condition to check if they are equal to 0
Step 6- If not, use the % operator and the carry flag to perform bitwise addition
Step 7-Display it as result
Step 8-STOP

Example 1

Here, the input is being entered by the user based on a prompt. You can try this example live in ourcoding ground tool .

import java.util.*;
public class AddBinaryNumbers {
   public static void main(String[] args) {
      long binary_input_1 , binary_input_2 ;
      System.out.println("Required packages have been imported");
      Scanner input = new Scanner(System.in);
      System.out.println("A reader object has been defined ");
      System.out.print("Enter the first binary number : ");
      binary_input_1 = input.nextLong();
      System.out.print("Enter the second binary number : ");
      binary_input_2 = input.nextLong();
      int i, carry ;
      i = 0;
      carry = 0;
      int[] binary_sum = new int[10];
      while (binary_input_1 != 0 || binary_input_2 != 0) {
         binary_sum[i++] = (int) (carry + (binary_input_1 % 10 + binary_input_2 % 10) % 2);
         carry = (int) ((binary_input_1 % 10 + binary_input_2 % 10 + carry) / 2);
         binary_input_1 = binary_input_1 / 10;
         binary_input_2 = binary_input_2 / 10;
      }
      if (carry != 0) {
         binary_sum[i++] = carry;
      }
      --i;
      System.out.print("\nThe sum of the binary numbers is: ");
      while (i >= 0) {
         System.out.print(binary_sum[i--]);
      }
      System.out.print("\n");
   }
}

Output

Required packages have been imported
A reader object has been defined
The first binary number is 10101
The second binary number is 10001
The sum of the binary is: 100110

Example 2

Here, the integer has been previously defined, and its value is accessed and displayed on the console.

public class AddingBinaryNumbers {
   public static void main(String[] args) {
      long binary_input_1 , binary_input_2 ;
      binary_input_1 = 10101;
      binary_input_2 = 10001;
      System.out.print("The first binary number is " + binary_input_1);
      System.out.print("\nThe second binary number is " + binary_input_2);
      int i, carry ;
      i = 0;
      carry = 0;
      int[] binary_sum = new int[10];
      while (binary_input_1 != 0 || binary_input_2 != 0) {
         binary_sum[i++] = (int) (carry + (binary_input_1 % 10 + binary_input_2 % 10) % 2);
         carry = (int) ((binary_input_1 % 10 + binary_input_2 % 10 + carry) / 2);
         binary_input_1 = binary_input_1 / 10;
         binary_input_2 = binary_input_2 / 10;
      }
      if (carry != 0) {
         binary_sum[i++] = carry;
      }
      --i;
      System.out.print("\nThe sum of the binary numbers is: ");
      while (i >= 0) {
         System.out.print(binary_sum[i--]);
      }
      System.out.print("\n");
   }
}

Output

The first binary number is 10101
The second binary number is 10001
The sum of the binary numbers is: 100110