Stuck on a simple problem: Find the sum of all the multiples of 3 or 5 below 1000.

Question

Hi need some help with the summing of this simple problem. Seems that it doesn't save on the arrays.
Here is the code:

using System;

namespace test
{
class Program
{
static void Main()
{
Program p = new Program();
p.sum(1000);

Console.ReadLine();
}

public void sum (int tal)
{
for (int i = 1; i < tal; i++)
{
int[] array= new int[1000];
if (i % 3 == 0 || i % 5 == 0)
{
array[i] += i;
Console.WriteLine(array[i]);
}
}
}
}
}

Can someone give me the guidance to complete this one!?

Best regards,

Datta Kharad · Answer

Hi Declare array outside the for loop and get another variable total for sum... You can display each number which is meet your condition ie multiple of 3 or 5 and Lastly display Sum of these numbers. Use this code:- using System; namespace test { class Program { static void Main() { Program p = new Program(); p.sum(1000); Console.ReadLine(); } public void sum (int tal) { long total = 0; int[] array= new int[1000]; //It does save in Array..(Here your problem get solved) for (int i = 1; i { if (i % 3 == 0 || i % 5 == 0) { array[i] += i; total = total + i; Console.WriteLine(array[i]); } } Console.WriteLine(Sum of multiple 3 or 5 below 1000= +total); } } }

Datta Kharad · Answer

Hi If your query resolved then mark as Correct Answer.

Zu Sung Park · Answer

Thank you so much! :) I used this tips since I wanted to use Array.

Zu Sung Park · Answer

Thank you so much! :) Good tips!

Armando Pinto · Answer

Hi. Looking at your code I'm not sure of what you want to do... If you want to get the total sum you should maybe do something like this: namespace test { class Program { static void Main(string[] args) { long totalSum = Sum(1000); Console.WriteLine(string.Format(Total sum: {0} totalSum)); Console.ReadLine(); } public static long Sum(int tal) { long total = 0; for (int i = 1; i { if (i % 3 == 0 || i % 5 == 0) { total += i; } } return total; } } }