# Project Euler Problem 1 – Multiples of 3 and 5

I was randomly searching for best place to learn “programming by doing” and I have found link on Project Euler. I really like the idea of the project and I decided to join. Here is a description of the first Project Euler problem:

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.

The problem is very easy. We are checking division of the numbers 3 and/or 5, the end number is not high and an idea of the sum is very clear. Despite the fact we need to brute-forcefully iterate all over the first 1000 numbers, I did not think much about any other complicated algorithm. The brute-force can be enough in this case.

## PHP:

```<?php
\$sum = 0;
for (\$i=0;\$i<1000;\$i++) {
if((\$i%3 == 0) OR (\$i%5 == 0)){
\$sum += \$i;
}
}
echo \$sum;
?>
```

## JAVA:

```public class Project_Euler_Problem_001 {

public static void main(String[] args) {

System.out.println("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.");
System.out.println("Find the sum of all the multiples of 3 or 5 below 1000.");

int sum = 0;
for (int i = 0; i<1000; i++) {
if((i%3 == 0) || (i%5 == 0)){
sum += i;
}
}
System.out.println("\n"+ "Sum is: " + sum);;
}
}```
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