redspider926/bowling

algorithm for bowling

Ten-Pin Bowling

In the game of ten-pin bowling, a player rolls a bowling ball down a lane to knock over pins. There are ten pins set at the end of the bowling lane. Each player has 10 frames to roll a bowling ball down a lane and knock over as many pins as possible. The first nine frames are ended after two rolls or when the player knocks down all the pins. The last frame a player will receive an extra roll every time they knock down all ten pins; up to a maximum of three total rolls.

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The Challenge

In this challenge you will be given a string representing a player's ten frames. It will look something like this: 'X X 9/ 80 X X 90 8/ 7/ 44' (in Java: "X X 9/ 80 X X 90 8/ 7/ 44"), where each frame is space-delimited, 'X' represents strikes, and '/' represents spares. Your goal is take in this string of frames into a function called bowlingScore and return the players total score.

Scoring

The scoring for ten-pin bowling can be difficult to understand, and if you're like most people, easily forgotten if you don't play often. Here is a quick breakdown:

Frames

In Ten-Pin Bowling there are ten frames per game. Frames are the players turn to bowl, which can be multiple rolls. The first 9 frames you get 2 rolls maximum to try to get all 10 pins down. On the 10th or last frame a player will receive an extra roll each time they get all ten pins down to a maximum of three total rolls. Also on the last frame bonuses are not awarded for strikes and spares moving forward.

In this challenge, three frames might be represented like this: 54 72 44. In this case, the player has had three frames. On their first frame they scored 9 points (5 + 4), on their second frame they scored 9 points (7 + 2) and on their third frame they scored 8 points (4 + 4). This is a very simple example of bowling scoring. It gets more complicated when we introduce strikes and spares.

Strikes

Represented in this challenge as 'X'

A strike is scored when a player knocks all ten pins down in one roll. In the first 9 frames this will conclude the players turn and it will be scored as 10 points plus the points received from the next two rolls. So if a player were to have two frames X 54, the total score of those two frames would be 28. The first frame would be worth 19 (10 + 5 + 4) and the second frame would be worth 9 (5 + 4).

A perfect game in bowling is 12 strikes in a row and would be represented like this 'X X X X X X X X X XXX' (in Java: "X X X X X X X X X XXX"). This adds up to a total score of 300.

Spares

Represented in this challenge as '/'

A spare is scored when a player knocks down all ten pins in two rolls. In the first 9 frames this will be scored as 10 points plus the next roll. So if a player were to have two frames 9/ 54, the total score of the two frames would be 24. The first frame would be worth 15 (10 + 5) and the second frame would be worth 9 (5 + 4).