As part of my effort to refresh my memory in the areas of algorithms, data structures and mathematics, I’m going to use problems from Project Euler. Now, let’s get to problem 1.

/*
Project Euler - Problem 1 - Multiples of 3 and 5 [ https://projecteuler.net/problem=1 ]
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. 
The sum of these multiples is 23.
Find the sum of all the multiples of 3 or 5 below 1000.

This is a generic implementation of the solution.
Input Format: 
The first line of the input contains the multiples ( 3 and 5 in our case).
The second line of input contains the upper bound (1000 in our case).
*/
public static void Problem1() {
	string multiplesRawInput = Console.ReadLine();
	int upperBound = int.Parse(Console.ReadLine());
	int[] multiples = new int[(multiplesRawInput.Split(" ".ToCharArray())).Count()];
	int i = 0;
	foreach(string multiple in multiplesRawInput.Split(" ".ToCharArray())) {
		multiples[i] = int.Parse(multiple);
		i++;
	}

	int result = 0;
	for (int j = 1; j < upperBound; j++) {
		if (((j % 3) == 0) || ((j % 5) == 0)) result = result + j;
	}
	Console.WriteLine(result);
}

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