while na pratica

<?php
header("Content-Type: text/html; charset=utf-8");
 $a = 20;

 while($a < 30){
    $a++;
 }
 var_dump($a);
echo "<br>";

$i = 0;

while ($i < 5){
    $i++;
    echo "<h{$i}>Iteraçao<h$i>";
}
echo "<br>";
 $a = 20;

 while($a <30):
    $a++;
    echo"{$a} ";
 endwhile;

 var_dump($a);
 echo"<br>";
 for ($i = 10; $i < 41; $i++){ // notase a diferença do laço ao printar na tela
    echo $i;
 }
 echo"<br>";
 $i = 9;
 while($i < 40):
    $i++;
    echo "{$i}";
 endwhile;
 echo "<br><br><h2>Estrutura de repetiçao</h2>";
$cont=-10;
while ($cont<=10){
    echo"loop=>{$cont}.<br>";;
    $cont++;
}
var_dump($cont);
//https://www.facebook.com/groups/353340335260087/


?>