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Sum the digits of an integer.

MaryEllen Volb
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Joined: Jan 31, 2001
Posts: 35
I have already gotten one good response to this one, but now I can't understand how to extract the digits so I can sum them together (2 + 3 + 4 =9). Anyone got any great idea?
Here's the code I already got:
public class Test{
public static void main(String[] args){
int i = 234;
private static void sumDigits(int digits){System.out.println("digits before calculation: " + digits);int sum = 0;
sum += digits % 10;
digits /= 10;
System.out.println("sum: " + sum);System.out.println("digits after calculation: " + digits);
}} Thanks!!!Mary Ellen
huiying li
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Joined: Feb 12, 2001
Posts: 68

MaryEllen Volb
Ranch Hand

Joined: Jan 31, 2001
Posts: 35
Thanks....I'll try it!!! Mary Ellen
Pat Barrett
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Joined: Jan 03, 2001
Posts: 63
The first thing is to separate the digits. If you take a 3 digit number and divide by 100, your answer will be a single digit representing the hundreds place. Now, if you take that same 3 digit number and get the modulus of a division by 100, you will be left with the tens and units places, represented as a 2 digit number. Take that 2 digit number, divide by ten and you'll have the 10's place, the modulus of the 2 digit number divided by 10 will be the units place.
Let's try 123..
123 / 100 = 1 ( the hundreds place )
123 % 100 = 23 ( the remainder )
23 / 10 = 2 ( the tens place )
23 % 10 = 3 ( the units place )
Sum up the hundreds, tens & units and you'll have your answer.

Pat B.
MaryEllen Volb
Ranch Hand

Joined: Jan 31, 2001
Posts: 35
Yes, it did help so much.....thanks....I wouldn't be getting thru my class if not for all the help I find here!!!

Mary Ellen
Vnese Programmer

Joined: Jul 14, 2013
Posts: 1
Thank you Mr/Ms Pat Barrett for the beneficial answer. I resolved the problem. Cheers!
I agree. Here's the link:
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