enterTheNumber

<form method = "get">
    <input type = "text" name = "elements"/>
    <input type = "submit"/>
</form>

<?php

if (isset($_GET['elements'])){
    $input = ($_GET['elements']);
    if ($input > 0 && $input < 10){
        echo "Correct value!";
    }
    else{
        echo "Invalid value!";
    }
}