for($头发 = 0;$头发 < 10000000000000000000;$头发++){
    echo $头发;
}

$满意 = false;
while(true){
    if($满意 == true){
        break;
    }
    echo '头发';
}

<?php
$黑发=100000;
$白发=500;
while($白发>0){
  $黑发+=200;
  $白发--;
}
echo "黑发：$黑发<br/>白发：$白发";