php in_array fails if array value contains true code example

Example 1: in_array php

<?php
$os = array("Apple", "Banana", "Lemon");
if (in_array("Apple", $os)) {
    echo "Yeah. Exist Apple";
}
if (!in_array("Buleberry", $os)) {
    echo "Oh, Don't Exist Blueberry!!!";
}
?>

Example 2: in_array

<?
in_array("Irix", $os);
?>