Another ancient discovery was the Polynesian game of ula maika, which also used pins and balls of stone. The stones were to be rolled at targets 60 feet away, a distance which is still one of the basic regulations of tenpins.
Bowling at tenpins probably originated in Germany, not as a sport but as a religious ceremony. Martin Luther is credited with settling on nine as the ideal number of pins.
Tracing history reveals the game moved through Europe, the Scandinavian countries and finally to the United States, where the earliest known reference to bowling at pins in America was made by author Washington Irving about 1818 in Rip Van Winkle.
Although the game was being played throughout the world, rules were different almost everywhere, and even basic equipment was not the same. In fact, why and when the 10th pin was added from the European game of ninepins to the American game of tenpins is still a mystery.
For each frame, a bowler is allowed a maximum of two rolls to knock down all ten pins. If the bowler knocks them all down on the first attempt, the frame is scored as a strike. If the bowler does not knock them down on the first attempt in the frame the bowler is allowed a second attempt to knock down the remaining pins. If the bowler succeeds in knocking the rest of the pins down in the second attempt, the frame is scored as a spare.
The score for a bowling game consists of sum of the scores for each frame. The score for each frame is the total number of pins knocked down in the frame, plus bonuses for strikes and spares. In particular, if a bowler scores a strike in a particular frame, the score for that frame is ten plus the sum of the next two rolls. If a bowler scores a spare in a particular frame, the score for that frame is ten plus the score of the next roll. If a bowler scores a strike in the tenth (final) frame, the bowler is allowed two more rolls. Similarly, a bowler scoring a spare in the tenth frame is allowed one more roll.
The maximum possible score in a game of bowling (strikes in all ten frames plus two extra strikes for the tenth frame strike) is 300.
The end of input is indicated by a single line containing the text Game Over (terminated with a newline).
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