Generate random seating assignments for a multi-session meeting.

gistfile1.txt

$personTableAssignments = generateTableAssignments(8, 8);

foreach ($personTableAssignments as $personTableAssignment) {
	echo (implode(', ', $personTableAssignment) . '<br />');
}

function generateTableAssignments($numSessions, $numTables)
{
	$numPeople = $numSessions * $numTables;
	$tableSessionCount = [];
	$personTableAssignments = [];
	
	for ($table = 0; $table < $numTables; $table++) {
		// keep a count of the number of people at each table for each session.
		$tableSessionCount[$table] = [0,0,0,0,0,0,0,0];
	}
	
	for ($person = 0; $person < $numPeople; $person++) {
		// keep track of which tables a person has been assigned to
		$personTableAssignments[$person] = [];
	}
	
	$numAssignmentsComplete = 0;
	$numAssignmentsNeeded = $numPeople * $numTables;
	
	while ($numAssignmentsComplete < $numAssignmentsNeeded) {
		$randomListOfPeople = range(0, $numPeople - 1);
		shuffle($randomListOfPeople);
		
		foreach ($randomListOfPeople as $randomPerson) {

			$randomListOfTables = range(0, $numTables - 1);
			shuffle($randomListOfTables);
			
			foreach (range(0, $numSessions - 1) as $sessionNumber) {
			
				foreach ($randomListOfTables as $table) {
					
					// make sure A) this person hasn't already been assigned to this table and
					// B) that this table isn't already full for the session
					if (!in_array($table, $personTableAssignments[$randomPerson]) && $tableSessionCount[$sessionNumber][$table] < 8) {
				
						$numAssignmentsComplete++;
						$personTableAssignments[$randomPerson][] = $table;
						$tableSessionCount[$sessionNumber][$table] += 1;
						break;
					}
				}
			}
		}
	}
	
	// convert 0 based table assignments to 1 based
	array_walk($personTableAssignment, function (&$x) { $x = $x + 1; });
	
	return $personTableAssignments;
}