A Young Man's Adventure in the World of Swords and Magic

A young man who was an avid math and programming enthusiast died suddenly and was body-swapped by a mysterious world traveler. Come to this sword and magic world full of magnificent fantasy and magnificent epics. What kind of miracles will the boy with maximal magic adaptability create with his wisdom and magic? Many years later, when he once again sees the magic he created exerting its supreme power in the hands of children, will he think of that afternoon when he was immersed in runes and formations?