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exercism fetch typescript circular-buffer

Circular Buffer

A circular buffer, cyclic buffer or ring buffer is a data structure that uses a single, fixed-size buffer as if it were connected end-to-end.

A circular buffer first starts empty and of some predefined length. For example, this is a 7-element buffer:

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[ ][ ][ ][ ][ ][ ][ ]

Assume that a 1 is written into the middle of the buffer (exact starting location does not matter in a circular buffer):

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[ ][ ][ ][1][ ][ ][ ]

Then assume that two more elements are added — 2 & 3 — which get appended after the 1:

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[ ][ ][ ][1][2][3][ ]

If two elements are then removed from the buffer, the oldest values inside the buffer are removed. The two elements removed, in this case, are 1 & 2, leaving the buffer with just a 3:

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[ ][ ][ ][ ][ ][3][ ]

If the buffer has 7 elements then it is completely full:

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[6][7][8][9][3][4][5]

When the buffer is full an error will be raised, alerting the client that further writes are blocked until a slot becomes free.

The client can opt to overwrite the oldest data with a forced write. In this case, two more elements — A & B — are added and they overwrite the 3 & 4:

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[6][7][8][9][A][B][5]

Finally, if two elements are now removed then what would be returned is not 3 & 4 but 5 & 6 because A & B overwrote the 3 & the 4 yielding the buffer with:

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[ ][7][8][9][A][B][ ]

Setup

Go through the setup instructions for TypeScript to install the necessary dependencies:

http://exercism.io/languages/typescript

Requirements

Install assignment dependencies:

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$ yarn install

Making the test suite pass

Execute the tests with:

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$ yarn test

Source

Wikipedia http://en.wikipedia.org/wiki/Binary_search_algorithm

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.