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# Stage 6, Working with functions: Confused

Hi,

I've passed the quiz, but I'm not sure how this works. Could someone please explain it to me?

```<?php

\$numbers = array(1,2,3,4);

\$total = count(\$numbers);

\$sum = 0;

\$output = "";

\$i = 0;

foreach(\$numbers as \$number) {

\$i = \$i + 1;

if (\$i < \$total) {

\$sum = \$sum + \$number;

}

}

echo \$sum;

?>
```

The options are: A-1234 B-4321 C-321 D-6

Hi Stephen,

Fixed markdown to show syntax highlighting. While you had the triple backticks, it was missing the php language specifier.

Hi Stephen,

The easiest way to work through these types of problems is with a sheet of paper, or text editor, to keep track of the values of variables through each iteration of the loop.

The short answer is that `i` gets incremented before it's checked against the length of the array. So, by the start of the 4th iteration of the loop, `i == 4` and the if statement evaluates to false. Therefore, the only numbers that got added from the array are 1, 2, and 3.

Hope this helps!

Think of `\$total` as just the number 4, and `i` starts at 0.

```Loop iteration 1:
i += 1
i == 1
i < 4 // True
add current number (1) to sum (0)
sum == 1

Loop iteration 2:
i += 1
i == 2
i < 4 // True
add current number (2) to sum (1)
sum == 3

Loop iteration 3:
i += 1
i == 3
i < 4 // True
add current number (3) to sum (3)
sum == 6

Loop iteration 4:
i += 1
i == 4
i < 4 // False
// sum remains at 6
```

Thank you, that explains a lot. I thought it was something like that, but the way you explained it helped.