Online PHP editor | output for jYpAE

<?php $dates[] = array("date" => "2016-02-18 02:00:00", "duration" => "600"); // 10 mins $dates[] = array("date" => "2016-02-18 02:05:00", "duration" => "300"); // 5 mins $dates[] = array("date" => "2016-02-18 02:10:00", "duration" => "600"); $dates[] = array("date" => "2016-02-18 02:15:00", "duration" => "300"); $dates[] = array("date" => "2016-02-18 02:20:00", "duration" => "600"); $dates[] = array("date" => "2016-02-18 02:25:00", "duration" => "300"); $dates[] = array("date" => "2016-02-18 02:30:00", "duration" => "600"); $alreadyChosenDates[] = array("date" => "2016-02-18 02:05:00", "duration" => "300"); // 10 mins function returnClosestTime($alreadyChosenDates, $dates){ // Set an array called $closestTime that has the time difference and the key $closestTime = [null, null]; // Check each element in array foreach($dates as $key => $date){ foreach($alreadyChosenDates as $chosenDates){ // Calculate difference between already chosen dates array and the dates array $diff = (strtotime($chosenDates["date"]) + $chosenDates["duration"]) - strtotime($date["date"]); if($diff < 0) $diff = $diff * -1; // If $closestTime is empty, populate it if($closestTime[0] === null) $closestTime = [$diff, $key]; // If $closestTime isn't empty and the current date's time difference // is smaller, populate $closestTime with the time difference and key else if($diff < $closestTime[0]) $closestTime = [$diff, $key]; } } return $dates[$closestTime[1]]; } $alreadyChosenDates[] = returnClosestTime($alreadyChosenDates, $dates); echo "<pre>"; print_r($alreadyChosenDates); echo "</pre>";