function lowercase_uppercase_characters_same_order($s) {
$len = strlen($s);
$lower_s = "";
$upper_s = "";
for ($i = 0; $i < $len; $i++) {
if ($s[$i] >= 'A' && $s[$i] <= 'Z') {
$upper_s = $upper_s . $s[$i];
}
if ($s[$i] >= 'a' && $s[$i] <= 'z') {
$lower_s = $lower_s . $s[$i];
}
}
return strtoupper($lower_s) == $upper_s;
}
$s = "pPHhpP"; // phpPHP
if (lowercase_uppercase_characters_same_order($s)) {
echo "Yes";
}
else {
echo "No";
}
/*
run:
Yes
*/