I was wondering why it wont change like this when the variables are already defined?

Question

<?php

//add 5 to integer one and substract 1 from integer 2
$integerOne = 1;
$integerTwo = 2;

$integerOne + 5;
$integerTwo - 1;
?>

```index.php
<?php

//Place your code below this comment
$integerOne = 1;
$integerTwo = 2;

$integerOne + 5;
$integerTwo - 1;
?>

Answer 1 · 2016-12-06T13:42:41Z

December 6, 2016 1:42pm

The problem is you are not actually changing the variables. When you use the variable you are using the value stored in the variable and not changing the value that the variable holds. If you want to change a variable then you need to reset it's value using the equal sign.

<?php
  $integerOne = 1;
  $integerTwo = 2;

// These two statements are equivalent and the simple add 1 plus 2.
// However, they don't store the value of 1 plus 2 anywhere so after 
// the statement execute the value 3 is just dumped from memory.

$integerOne + $integerTwo;
1 + 2;

// In order to save the value of the statements you need to put them in
// a variable.

$newVariable = $integerOne + $integerTwo;

// now $newVariable is equal to 3.


// In order to change the value of an existing variable you need to use the equal sign

$integerOne = $integerOne + $integerTwo;

// now the value of $integerOne is 3, because 2 plus 1 is three.
// Also, you can rewrite the above statement like so.

$integerOne += $integerTwo;

//this is just a shorthand way of writing $integerOne = $integerOne + $integerTwo;

Welcome to the Treehouse Community

Looking to learn something new?

Ismail Shabbir

Ismail Shabbir

I was wondering why it wont change like this when the variables are already defined?

1 Answer

Andrew Shook

Andrew Shook