Calculation (card game)

Calculation is a solitaire card game for one player, played with a standard pack of 52 cards. It is also known as Broken Intervals, Hopscotch and Four Kings Solitaire, and it belongs to the Sir Tommy family of patience games. The game is said to have its origin in France, where it is called La Plus Belle. An ace, a two, a three and a four are taken out of the pack and laid out as four foundations. The ace foundation is built up one card at a time to the king, the two foundation by twos, the three foundation by threes and the four foundation by fours, until each of them reaches a king. Cards turned up from the stock go onto any of four tableau piles, which start empty, and the top card of a pile may move to a foundation when it is the next card in that foundation's sequence. The game is won when every card has been played onto the foundations and lost when no further play is possible. Variants add a one-card waste pile, leave out the four starting cards or use only three tableau piles.