Java program to find Harshad or Niven number from 1 to 100

This tutorial is to find Harshad or Niven number in Java. A Harshad or number or even number is a number that is divisible by its digits.
For example, 63 : The sum of its digits is 6+3 = 9. 63 is divisible by 9 . So it is a Harshad number. But 64 is not. Because 6+4 =10 and 64%10 or reminder is not zero. We will write one Java program to find all Harshad numbers starting from 1 to 100.
All one digits numbers are Harshad number, because each number is divided by that number.

Java program to find all Harshad/Niven numbers from 1 to 100 :

/*
 * Copyright (C) 2017 codevscolor.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * Class to find Harshad / Niven number from 1 to 100
 */
public class Test {

    static void print(String value) {
        System.out.print(value);
    }

    /**
     * find sum of digits of a number
     *
     * @param number : number to find the sum of its digit
     * @return : sum of all digits
     */
    static int findSumOfDigits(int number) {
        int sum = 0;
        while (number > 0) {
            sum += number % 10;
            number /= 10;
        }
        return sum;
    }

    public static void main(String[] args) {

        for (int i = 1; i < 101; i++) {
            if (i % findSumOfDigits(i) == 0) { //if sum of digits can divide the number, then it is a Harshad number
                print(i + " ");
            }
        }

    }
}

Output :

1 2 3 4 5 6 7 8 9 10 12 18 20 21 24 27 30 36 40 42 45 48 50 54 60 63 70 72 80 81 84 90 100 

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