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PHP

Alex Bauer
Alex Bauer
9,426 Points
Posted by Alex Bauer
Alex Bauer
9,426 Points

Can someone please help me understand foreach functions?

I got this problem on a quiz and the answer didn't make any sense to me.

$numbers = array(1,2,3,4); $total = count($numbers); $sum = 0; $loop = 0;

foreach($numbers as $number) { $loop = $loop + 1; if ($loop < $total) { $sum = $sum + $number; } }

echo $sum; //somehow the answer is 6.

1 Answer

richporter
richporter
16,727 Points

The loop runs for each item in the array, so 4 times.

But on the last iteration of the loop, $loop is not less than $total (it is equal), so $sum isnt modified.

So 1 + 2 + 3 = 6

<?php
$numbers = array(1,2,3,4);

$total = count($numbers);
$sum = 0;
$loop = 0;

foreach($numbers as $number){
  $loop = $loop + 1;
  if ($loop < $total){
      $sum = $sum + $number;
    }
}

echo $sum;
Alex Bauer
Alex Bauer
9,426 Points
Alex Bauer
Alex Bauer
9,426 Points

but if $sum wasn't modified then wouldn't it still be 0? Also why wasn't 4 included when adding the numbers together in the array?

richporter
richporter
16,727 Points

$sum is modified on the 1st, 2nd and 3rd iteration of the loop.

1st time $sum is 0: 0 + 1

2nd time $sum is 1: 1 + 2

3rd time $sum is 3: 3 + 3

On the 4th iteration, $loop is not less than $total they are equal, so $sum isnt modified and the 4 is not added.

Alex Bauer
Alex Bauer
9,426 Points
Alex Bauer
Alex Bauer
9,426 Points

Okay! Now I finally understand thank you, this was a big help!