Why is the zero-indexed item in my $array not recognised?

<?php
    $array = ["1", "3", "5", "7", "9"];

    $compare = ["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"];

    foreach ($compare as $c) {
        echo '$array ';
        if (array_search($c, $array, true)) {
            echo 'does ';
        } else {
            echo 'does not ';
        }
        echo "contain $c <br>";
    }