Java Exercises: Convert a decimal number to binary numbers

Java Basic: Exercise-19 with Solution

Write a Java program to convert a decimal number to binary number.

Decimal number: The decimal numeral system is the standard system for denoting integer and non-integer numbers. It is also called base-ten positional numeral system.

Binary number: In digital electronics and mathematics, a binary number is a number expressed in the base-2 numeral system or binary numeral system. This system uses only two symbols: typically 1 (one) and 0 (zero).

Test Data:
Input a Decimal Number : 5

Pictorial Presentation: of decimal to binary number

Sample Solution:

Java Code:

import java.util.Scanner;
public class Exercise19 {
      public static void main(String args[])
    {
        int dec_num, quot, i=1, j;
        int bin_num[] = new int[100];
        Scanner scan = new Scanner(System.in);
		
        System.out.print("Input a Decimal Number : ");
        dec_num = scan.nextInt();
		
        quot = dec_num;
		
        while(quot != 0)
        {
            bin_num[i++] = quot%2;
            quot = quot/2;
        }
		
        System.out.print("Binary number is: ");
        for(j=i-1; j>0; j--)
        {
            System.out.print(bin_num[j]);
        }
        System.out.print("\n");
    }
}

Sample Output:

Input a Decimal Number : 5                                                                                    
Binary number is: 101  

Flowchart:

Java Code Editor:

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