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Lucas Santos
19,315 PointsCan someone please explain this code
Im stuck on this quiz and I believe it's asking me what this code would output on the screen.
<?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) {
$output = $number . $output;
}
}
echo $output;
?>
3 Answers
Dino Paškvan
Courses Plus Student 44,108 PointsWhen this particular piece of code starts executing, there are four variables initialized at the top. First, you can ignore $sum because it's not used elsewhere in the code. $i is 0, $total is 4 because there are 4 elements in the $numbers array, and $output is an empty string.
On the first iteration of foreach, $i gets immediately increased to 1. Then we check if it's smaller that $total. Because it is, the current number from the $numbers array (in this case it's the first element — 1) gets concatenated with the $output and the resulting string is assigned as the new value of the $output variable, which now equals to "1".
On the second iteration, $i is increased to 2. It's still smaller than $total, so now the second element of the array (2) is concatenated with $output ("1") and the resulting string ("21") is assigned as the new value of $output.
The same is true for the third iteration, only now the resulting string is "321".
In the fourth iteration, $i is now 4 and as it's not smaller than $total, no value re-assignment of $output happens.
So, the final output is the resulting string from the third iteration: 321.
Guillaume Maka
Courses Plus Student 10,224 Points<?php
// declare an array of 4 numbers
$numbers = array(1,2,3,4);
// assign the length of $number array to $total -> 4
$total = count($numbers);
// declare a variable $sum and initialize it to 0
$sum = 0;
// declare a variable $output and initialize it to an empty string
$output = "";
// declare a variable $i and initialize it to 0
$i = 0;
// do a foreach loop to grab each element in the array
foreach($numbers as $number) {
// track how many element we have already take
// ex: at the first iteration, $i = 0 + 1
$i = $i + 1;
// check we don't exceed the total sze of the array
// ex: at the first iteration, $i = 1 , $total = 4, so 1 < 4 then enter into the if statement
if ($i < $total) {
// concatenate the given $number to the $output
// ex: at the first iteration, $number = 1, $ouptut = ''
$output = $number . $output;
// $output = '1'
}
}
// print the output to the screen
// $output = '321'
echo $output;
?>
Hope that will help you.
Lucas Santos
19,315 PointsThanks a lot this helps!
Lucas Santos
19,315 PointsThanks a lot this helps!
Lucas Santos
19,315 PointsLucas Santos
19,315 Pointscrystal clear
Lucas Santos
19,315 PointsLucas Santos
19,315 PointsHey so when ever you concatenate a number or value to an empty variable it will always add it to the left meaning the beginning of the empty string rite? I would think it would be like reading and it adds the numbers to the rite like 123 instead of 321 but I guess not.
Guillaume Maka
Courses Plus Student 10,224 PointsGuillaume Maka
Courses Plus Student 10,224 PointsTo get 123 you just need to do the opposite
$output = $output . $number;That was your question ?
Lucas Santos
19,315 PointsLucas Santos
19,315 PointsI see ok got it thanks!