php基础11：运算符

<?php
    $a = 5;
    $b = ++$a;
    echo '$a'.$a;
    echo "<br>";
    echo '$b'.$b;
    echo "<hr>";

    $x = 10;
    $y = $x++;
    echo '$x'.$x;
    echo "<br>";
    echo '$y'.$y;
?>