ALL THIS GENIUS SPOILERI doubt I can explain the card counting thing well because it didn't really sink into my head either. I'd go back to try and understand it fully but it's a bit late for me to try. My basic processing of it was that there are 4 card decks with cards numbering from 210. If you add the value of the cards found in each deck, 2+3+4+5+6+7+8+9+10 = 55. Since there are four decks, 4x55 = 220. As the shared cards were revealed and after he saw what Sangmin had, Yohwan deducted the total from 220. So if the first shared cards were 5 and 6 and Sangmin's card was 8, he would calculate 220(5+6+8) = 201. He'd use some of his chips to keep track of it as the rounds went on, but I don't recall how he did this exactly. Since he kept track of all the card values up until the end, the maths told him that after subtracting the final pair of shared cards and Sangmin's last card, it left a value of 2 remaining, so that was the card he must have. If that makes no sense, I apologise, but if if it does, excuse me while I give myself a pat on the back for my late night comprehension.
As for the end result, I'm glad Sangmin won. Honestly, Yohwan did not deserve to be there at all. He was terrible at the main matches, would make deals with people and break them immediately for no discernible reason, this includes himself and the strategies he would come up with and then not follow. Yes, he is incredibly strong in head-to-head matches, but that's as far as it goes. It was said that his partner wanted him to go on so he could improve his social skills and improve; he did not demonstrate anything indicating he was learning or adapting. In fact, he demonstrated the exact opposite by sucking any fun out of a lot of games for his fellow contestants and viewers by intentionally tanking in games and, in some cases, bringing others down with him.
As soon as Texas Hold 'em showed up I knew Yohwan had that game won considering he's a professional poker player. I didn't pay much attention to how he did it, but that was my understanding of the card counting. Basically adding up the sum of all the seen cards so he could figure out what the very last card was. The cards in the deck were 1-10, but it was late so I don't blame you.
I'm happy for Sangmin. Like Jinho said, I felt he played the most genius-like throughout the season, winning most of the games. A lot of the reasons he won is because of the deals he made, but I feel like that's a big part of the game and he was better than anyone else at being able to suss out who could help him the most and what he could offer them in return. He certainly deserved it much more than Yohwan.
I'm happy for Sangmin. Like Jinho said, I felt he played the most genius-like throughout the season, winning most of the games. A lot of the reasons he won is because of the deals he made, but I feel like that's a big part of the game and he was better than anyone else at being able to suss out who could help him the most and what he could offer them in return. He certainly deserved it much more than Yohwan.