Biến nào có tên sai?

php

<?php

$x=array(1,3,2,3,7,8,9,7,3);

$y=array_count_values($x);

echo $y[8]

?>

php

<?php

$x="101.5degrees";

(double)$x;

(int)$x;

echo (string)$x;

?>

php

<?php

$father = "mother";

$mother = "son";

echo $$father;

?>

php

<?php

$arr = array(5 => 1, 12 => 2);

$arr[] = 56;

$arr["x"] = 42;

echo var_dump($arr);

?>

php

<?php

$color = "maroon";

$var = $color[2]

echo "$var";

?>

php

<?php

$op2 = "blabla";

function foo($op1)

{

echo $op1;

echo $op2;

}

foo("hello");

?>

php

<?php

echo ord("hi");

?>

php

<?php

echo ucwords("i love my country");

?>

php

<?php

$people = array("Peter", "Susan", "Edmund", "Lucy");

echo pos($people);

?>