related #40

lib/php/calender/src/Entity/CalendarInfo.php

@@ -85,7 +85,7 @@ class CalendarInfo
     public function getNextWeek(int $week)
     {
         // 次の週
-        if ($week < ($this->num_of_weeks - 1)) {
+        if ($week < ($this->num_of_weeks)) {
             return [
                 'year' => $this->year,
                 'month' => (int)$this->month,