Who knows how to turn the lunar calendar into the solar calendar?

Mind is ok, but you must memorize the laws of the old calendar and the solar calendar. The solar calendar is simple, but the old calendar is more complicated, because there is no trial law of the size of the moon (the internal method is very troublesome). I usually remember the solar calendar and the old calendar of the last year or months from the perpetual calendar. You can refer to the mysterious yellow calendar to download.