[PHP] another simple array question

[cybermalandro cybermalandro]

I have an array with indexes 0 to 4 and I want to delete an element of the
array if the index is equals 4. I want to delete the variable key and value.
What is the best way to do so?

foreach ($values as $key => $val){

if ($key == "0") {
//
}
if ($key == "3") {
//
}
if ($key == "4") {
//delete value from array

}
}

Thanks!!!!!