try to solve GalacticDTH challenge

dappcamp_challenge_galacticDTH.php

<?php

/*
 * Complete the 'getMinClicks' function below.
 *
 * The function is expected to return an INTEGER.
 * The function accepts following parameters:
 *  1. INTEGER lowest_channel
 *  2. INTEGER highest_channel
 *  3. INTEGER_ARRAY blocked_channels
 *  4. INTEGER_ARRAY channel_sequence
 */


function getMinClicks($lowest_channel, $highest_channel, $blocked_channels, $channel_sequence): int {
  $total = 0;
  $current = $lowest_channel;
  $before = 0;
  foreach ($channel_sequence as $target) {
    $same = $target == $current ? 0 : null;
    $previous = $target == $before ? 1 : null;
    $manually = count(str_split($target));

    $forward = 0;
    $i = $current;
    do {
      $i++;
      if ($i > $highest_channel) {$i = $lowest_channel;}
      if ($i < $lowest_channel) {$i = $highest_channel;}

      if (!in_array($i, $blocked_channels)) {
        $forward++;
      }
    } while ($i !== $target);

    $backward = 0;
    $i = $current;
    do {
      $i--;
      if ($i > $highest_channel) {$i = $lowest_channel;}
      if ($i < $lowest_channel) {$i = $highest_channel;}

      if (!in_array($i, $blocked_channels)) {
        $backward++;
      }
    } while ($i !== $target);

    $values = [$same, $previous, $manually, $forward, $backward];
    $values = array_filter($values);
    $total += min($values);

    $before = $current;
    $current = $target;
  }

  return $total;
}

$fptr = fopen(getenv("OUTPUT_PATH"), "w");

$first_multiple_input = explode(' ', rtrim(fgets(STDIN)));

$lowest_channel = intval($first_multiple_input[0]);

$highest_channel = intval($first_multiple_input[1]);

$blocked_channels_count = intval(trim(fgets(STDIN)));

$blocked_channels_temp = rtrim(fgets(STDIN));

$blocked_channels = array_map('intval', preg_split('/ /', $blocked_channels_temp, -1, PREG_SPLIT_NO_EMPTY));

$channel_sequence_count = intval(trim(fgets(STDIN)));

$channel_sequence_temp = rtrim(fgets(STDIN));

$channel_sequence = array_map('intval', preg_split('/ /', $channel_sequence_temp, -1, PREG_SPLIT_NO_EMPTY));

$min_clicks = getMinClicks($lowest_channel, $highest_channel, $blocked_channels, $channel_sequence);

fwrite($fptr, $min_clicks . "\n");

fclose($fptr);