Calculation is a different sort of solitaire card game. The only other solitaire game I can think of that is similar is Colorado Solitaire. Calculation has 5 piles that are first in first out. In other words the last card you put on the pile is the first one you have to take out. You can not move any cards between the piles, they have to go from the piles into the foundations. You must take a card off of the stock pile and place it either directly into a foundation, or into one of the piles. You don't have to worry about suit in the game at all. When you put cards into the foundations you have to put them in alternating numbers. The first foundation puts the cards in order into the piles. The second foundation puts the cards in adding 2 to the value on the top card. The 3rd foundation you must add 3 to the value on the top card, and the fourth foundation you must add four. To make this process easier I put the number of the next card you have to put into the pile on the left of the foundation. The challenge is getting cards into the piles in an order that is useful in putting all the cards into the foundations.