CodeGym/Help with Java Tasks/Sum of the digits of a three-digit number

Level 4

Karlovac

19.11.2018
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13comments

Sum of the digits of a three-digit number

Question about the task

Java Syntax, Level 3, Lesson 12

Under discussion

Whats wrong with my code? Could anyone help!

Write the code for sumDigitsInNumber(int number). The method takes a three-digit whole number. You need to calculate the sum of the digits of this number, and then return the result.

Consider this example:
The sumDigitsInNumber method is called with the argument 546.

Example output:
15

Requirements:

The program must not read data from the keyboard.
The sumDigitsInNumber(int) method must be public and static.
The sumDigitsInNumber method must return an int.
The sumDigitsInNumber method should not display anything.
The sumDigitsInNumber method must return the sum of all digits in the parameter number.

package com.codegym.task.task01.task0132; /* Sum of the digits of a three-digit number */ public class Solution { public static void main(String[] args) { System.out.println(sumDigitsInNumber(546)); } public static int sumDigitsInNumber(int number) { int sum ; int n; sum =0; n = number%10; sum = sum + number % 10; number = number /10 + number /10 + number /10; return sum; } }

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Mnemonic

Level 9 , london, United Kingdom

27 July 2020, 17:15

public static int sumDigitsInNumber(int number) { int firstDigit = Integer.parseInt(Integer.toString(number).substring(0, 1)); int secondDigit = Integer.parseInt(Integer.toString(number).substring(1, 2)); int thirdDigit = Integer.parseInt(Integer.toString(number).substring(2, 3)); int newNum = firstDigit + secondDigit + thirdDigit; return newNum; }

Ahmad Essam

Level 18 , Cairo, Egypt

21 July 2020, 19:48

Try this solution inside the method write { return (number%1000/100) + (number%100/10) + (number%10); // it will work with you } some explanation for my code : (number % 1000 / 100) => this formula simply helped us to get the first number from left I can't dive deeper in it but trust me by the time you will understand it will and by the same token the second formula for the second number from the left. I hope my answer has assisted anyone. Happy Coding fellows!

Ryan Ceasar Borromeo

Level 7 , Makati, Philippines

16 March 2020, 09:30

package com.codegym.task.task01.task0132;

/*
Sum of the digits of a three-digit number

*/

public class Solution {
    public static void main(String[] args) {
        System.out.println(sumDigitsInNumber(546));
    }

    public static int sumDigitsInNumber(int number) {

        int num = number;
        int sum = 0;
        while (num > 0) {
            sum = sum + num % 10;
            num = num / 10;
        }

        return sum;
    }
}

hidden #10576927

Level 4

14 January 2020, 17:15

as a complete beginner this works good for me: public static int quersummeBerechnen(int zahl) { //schreib hier deinen Code int a, b, c, d; a = zahl / 100; b = (zahl / 10) - (10 * a); c = zahl - (a * 100) - (b * 10); d = a + b + c; return d;

Vicks

Level 4 , Mumbai, India

11 October 2019, 05:28

import java.util.*; public class Solution { public static void main(String[] args) { System.out.println(sumDigitsInNumber(546)); } public static int sumDigitsInNumber(int number) { //write your code here int num=0; List<Integer> digits = new ArrayList<>(); while(number > 0) { digits.add(number % 10); number /= 10; } for(int i=0;i<digits.size();i++){ num=num+ digits.get(i); } return num; } }

Matjes

Level 12 , Prague, Hungary

18 August 2019, 15:07

I did this way: 1) converted int to String => using String.valueOf(number); 2) converted each number to a char => using charAt(); // for example char c1 = s.charAt(0); 3) converted char to int => using Character.getNumericValue // for example Character.getNumericValue(c1); 4) the rest is easy with a simple math calculation I hope this helps. Good luck!

Deborishi Ganguly

Level 4 , Barpeta, India

3 June 2019, 21:33

Try Recursion, the food of the Gods.... return number == 0 ? 0 : number % 10 + sumDigitsInNumber(number / 10);

Gabriella LaPlace

Level 16 , Basseterre, Saint Kitts and Nevis

4 July 2019, 13:28

Thank you.

Rahul Sakhare

Level 5 , Pune, Indian

10 January 2019, 11:42

Best way to find the digit at each place..(tens..100th.. and unit..) and then add them by using % operator.. is the best any easy way.. number%10+((number/10)%10)+((number/100)%10);

Hashirama

Level 26 , Port-Harcourt, Nigeria

27 December 2018, 17:12

Try this: Add remainder of dividing the parameter number by 10 to sum. Then equate the parameter number to the division of the parameter number by 10. Repeat this step 3 times and you should have your sum as 15 This should be of help if you understand! int sum = number%10; number = number/10; repeat this 3 times.

Filip

Level 4 , Karlovac, Croatia

19 November 2018, 14:06

Thankssss!