my_submission_1.php

<?php
[$s, $l, $r] = explode(' ', file_get_contents('php://stdin'));
if($l <= $s && $s <= $r) printf("%d\n", $s);
else if($l > $s) printf("%d\n", $l);
else printf("%d\n", $r);

my_submission_2.php

<?php
[$s, $l, $r] = explode(' ', file_get_contents('php://stdin'));
$x = $s;
while(!isStopPosition($x, $l, $r)) {
  if($x < $l) $x += 1;
  else if($x > $r) $x -= 1;
}
printf("%d\n", $x);

function isStopPosition($pos, $l, $r): bool
{
  return $l <= $pos && $pos <= $r;
}