sum of digits in java

long number, sum;
Scanner sc = new Scanner(System.in);
System.out.println("Enter any DIGIT number: ");
number = sc.nextLong();
sc.close();
// For Logic for adding all digits in the given number
for (sum = 0; number != 0; number /= 10) {
	sum += number % 10;
	}
System.out.println("ForLoop Sum of ALL digits: " + sum);

import java.io.*;
public class sd
{
  public static void main(String [] args)throws IOException
  {
     InputStreamReader hi = new InputStreamReader(System.in);
        BufferedReader in = new BufferedReader(hi);
        System.out.println("Enter the number");
        int num=Integer.parseInt(in.readLine());
    int sum=0;
    while(num>=0)
    {
      int rem=n;
      sum+=rem;
      int quo=n/10;
      n=quo;
    }
    System.out.println(sum);
  }
}

public class SumNatural {

    public static void main(String[] args) {

        int num = 100, sum = 0;

        for(int i = 1; i <= num; ++i)
        {
            // sum = sum + i;
            sum += i;
        }

        System.out.println("Sum = " + sum);
    }
}

//To find the sum of even digits in a given Number

    public static int getEvenDigitSum(int number){
        if(number<0){
            return -1;
        }
        int finalNumber=0;
        while(number>0){
           if((number%10)%2==0){
               finalNumber+=number%10;

           }
           number=number/10; //takes out last digit to test the next digit


        }
        return finalNumber;
    }
//Output: ex:number=12323 -- Ans: 4