One possible solution for problem 1 on the Project Euler website

ProblemOne.cpp

/*
 * Project Name:            Problem One
 * Solution Name:           Problem One
 * Original creation date:  03/07/2011
 * Edit date:               18/01/2013
 * Programmer name:         Jamie Taylor (aka "GaProgMan")
 * File name:               ProblemOne.cpp
 *
 * Purpose of the project:
 *  This code is my solution for "Problem One" listed on
 * Project Euler. It is based on my version of the classic
 * "FizzBuzz" problem - more on which can be found at a
 * Coding Horror article called "Why Programmers can't
 * Program" by Jeff Attwood, here: http://bit.ly/cakJHF
 * For my solution to the "FizzBuzz" problem, you can
 * read my blog entry here:
 *    http://wp.me/s19MGD-fizzbuzz - "FizzBuzz" by Jamie Taylor
 *  The original problem is listed in the comment block below
 *
 * Problem Discussion:
 *   Problem One, from Project Euler. URL:
 *   http://projecteuler.net/index.php?section=problems&id=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.
 *
 *    GNU Copyright information
 *    Copyright 2011 Jamie Taylor <jamie@taylorj.org.uk>
 *
 *    This program is free software; you can redistribute
 *        it and/or modify it under the terms of the GNU General
 *        Public License as published by the Free Software
 *        Foundation; either version 2 of the License, or (at
 *	your option) any later version.
 *
 *	This program is distributed in the hope that it will
 *	be useful, but WITHOUT ANY WARRANTY; without even the
 *	implied warranty of MERCHANTABILITY or FITNESS FOR A
 *	PARTICULAR PURPOSE.  See the GNU General Public
 *	License for more details.
 *
 *	You should have received a copy of the GNU General
 *	Public License along with this program; if not, write
 *	to the Free Software Foundation, Inc., 51 Franklin
 *	Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/

#include <iostream>

using namespace std;
int main () {
  int sum = 0;
  for ( int i = 1; i <= 999; i++ ) {
    if ( i % 3 == 0 ) {
	  sum += i;
	}
	else if (i % 5 == 0){
	  sum += i;
	}
  }
  cout << "\The total of all multiples of 3 or 5 below 1000 is " << sum << endl;
  char ch;
  cin >> ch;
  return 0;
}