DecimalToBinary.java

import java.util.Scanner;

public class DecimalToBinary {
    public static void main(String[] args)
    {
        Scanner scanner = new Scanner(System.in);
        //int decimalNumber = 1024; // output is 10000000000
        int decimalNumber = scanner.nextInt();
        System.out.println(convertDecToBinTypically(decimalNumber));
        System.out.println(convertDecToBinWithRecursion(decimalNumber));
    }
    private static String convertDecToBinWithRecursion(int decimalNumber) {
        if (decimalNumber == 0) return "0";
        else if (decimalNumber == 1) return "1";
        return convertDecToBinWithRecursion(decimalNumber/2) + decimalNumber%2;
    }
    private static String convertDecToBinTypically(int decimalNumber) {
        String convertedToBinary = "";
        while (decimalNumber != 0) {
            if (decimalNumber%2 ==1) convertedToBinary = "1"+convertedToBinary;
            else convertedToBinary = "0"+convertedToBinary;
            decimalNumber /= 2;
        }
        return convertedToBinary == "" ? "0" : convertedToBinary;
    }
}