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<?php function daysInWeek($weekNum) { $result = array(); $datetime = new DateTime('00:00:00'); $datetime->setISODate((int)$datetime->format('o'), $weekNum, 1); $interval = new DateInterval('P7D'); $week = new DatePeriod($datetime, $interval, 52); foreach($week as $day){ $result[] = $day->format('D d m Y H:i:s'); } return $result; } //and the difficult ones:- var_dump(daysInWeek(1));

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