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How do I justify content in string using PHP?
How do I use the str_pad() function to justify content in a string?
You can use the str_pad() function like this: 
```php
$string = "Hello";
$padding = "-";
$justified_string = str_pad($string, 10, $padding, STR_PAD_LEFT);
echo $justified_string;
```
This code will output: "-----Hello"