find the sum of the multiples of 3 and 5 below 1000

Question

Ok guys, so I\'m doing the Project Euler challenges and I can\'t believe I\'m stuck on the first challenge. I really can\'t see why I\'m getting the wrong answer despite my

Answer 1

If number is 10 then multiple of 3 is 3,6,9 and multiple of 5 is 5,10 total sum is 33 and program gives same answer:

package com.parag;

/*
 * @author Parag Satav
 */
public class MultipleAddition {

    /**
     * @param args
     */
    public static void main( final String[] args ) {
    // TODO Auto-generated method stub

    ArrayList x = new ArrayList();
    ArrayList y = new ArrayList();
    int totalforthree = 0;
    int totalforfive = 0;
    int number = 8;

    int total = 0;

    for ( int temp = 1; temp <= number; temp++ ) {
        if ( temp % 3 == 0 ) {
            x.add( temp );
            totalforthree += temp;
        }

        else if ( temp % 5 == 0 ) {
            y.add( temp );
            totalforfive += temp;
        }
    }

    total = totalforfive + totalforthree;
    System.out.println( "multiples of 3 : " + x );
    System.out.println( "multiples of 5 : " + y );
    System.out.println( "The multiples of 3 or 5 up to " + number + " are: " + total );

}

}