Euler problem #1 - Spoiler Alert!

[J. Kevin Robbins]

I've finally signed up for the Euler project to improve my math and programming skills. I'm interested in feedback on my first solution. I'm not looking for the fastest solution or the least number of lines of code, but rather using sound coding practices that can be applied to any problem.

Now, how could I go about improving this code?

package my.euler.com;

/**
 * Euler 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.
 *
 */

public class Euler01 {

    private static final int UPPER_LIMIT = 1000;
    private static final int FIRST_NUM = 3;
    private static final int SECOND_NUM = 5;

    public static void main(String[] args) {
        final int result = crunchNumbers(UPPER_LIMIT);
        System.out.println("total is " + result);
    }

    private static int crunchNumbers(int limit) {
        int total = 0;
        int numberToTest = 1;
        for (int i = 0; i < limit - 1; i++) {
            if ((numberToTest % FIRST_NUM) == 0 || (numberToTest % SECOND_NUM) == 0) {
                total += numberToTest;
            }
            numberToTest++;
        }
        return total;
    }
}

[Matthew Brown]

One thing that springs to mind is that you're effectively using two variables, i and numberToTest, for one purpose (iterating across the required range). That's more error prone because you've got to keep them in sync. I'd suggest just using numberToTest and looping from 1 to limit.

[J. Kevin Robbins]

Thanks, excellent advice. This is why I like to ask for a different perspective on things. New code:

package my.euler.com;

/**
 * Euler 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.
 *
 * @author ZA15426
 */
public class Euler01 {

    private static final int UPPER_LIMIT = 1000;
    private static final int FIRST_NUM = 3;
    private static final int SECOND_NUM = 5;

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        final int result = crunchNumbers(UPPER_LIMIT);
        System.out.println("total is " + result);
    }

    private static int crunchNumbers(int limit) {
        int total = 0;        
        for (int numberToTest = 1; numberToTest < limit; numberToTest++) {
            if ((numberToTest % FIRST_NUM) == 0 || (numberToTest % SECOND_NUM) == 0) {
                total += numberToTest;
            }
        }
        return total;
    }
}