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

Zu Sung Park

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,

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Datta Kharad15y ago
Accepted 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 i,e 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 < tal; 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);
}
}
}
0
Datta Kharad15y ago
Hi
If your query resolved then mark as Correct Answer.
0
Zu Sung Park15y ago
Thank you so much! :) I used this tips since I wanted to use Array.
0
Zu Sung Park15y ago
Thank you so much! :) Good tips!
0
Armando Pinto15y ago
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 < tal; i++)
                {
                        if (i % 3 == 0 || i % 5 == 0)
                        {
                                total += i;
                        }
                }

                return total;
        }
   }
}
0