Java Program to Convert Decimal to Binary and Count the Number of 1s

This is a Java Program to Convert a Decimal Number to Binary & Count the Number of 1s.

Enter any integer as an input. Now we convert the given decimal input into a binary number with the help of division and modulus operations along with loops and if conditions to get the desired output.

Here is the source code of the Java Program to Convert a Decimal Number to Binary & Count the Number of 1s. The Java program is successfully compiled and run on a Windows system. The program output is also shown below.

  1. import java.util.Scanner;
  2. public class Convert
  3. {
  4.     public static void main(String[] args) 
  5.     {
  6.         int n, count = 0, a;
  7.         String x = "";
  8.         Scanner s = new Scanner(;
  9.         System.out.print("Enter any decimal number:");
  10.         n = s.nextInt();
  11.         while(n > 0)
  12.         {
  13.             a = n % 2;
  14.             if(a == 1)
  15.             {
  16.                 count++;
  17.             }
  18.             x = a + "" + x;
  19.             n = n / 2;
  20.         }
  21.         System.out.println("Binary number:"+x);
  22.         System.out.println("No. of 1s:"+count);
  23.     }
  24. }


$ javac
$ java Convert
Enter any decimal number:25
Binary number:11001
No. of 1s:3

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Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

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