61 lines
1.0 KiB
Markdown
61 lines
1.0 KiB
Markdown
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## How the fast iterator works
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Consider the following example, where we have `6` iterators, sorted from
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left to right in ascending order.
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Our 'primary' `A` iterator is on the left, containing the elements `[0,1,8]`
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```
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A B C D E F
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0 1 2 4 7 9
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1 2 9 - 14 13
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8 8 - 15 15
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- - - 16
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-
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```
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When we call `Next` on the primary iterator, we get (ignoring the future keys)
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```
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A B C D E F
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1 1 2 4 7 9
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```
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We detect that we now got an equality between our element and the next element.
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And we need to continue `Next`ing on the next element
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```
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1 2 2 4 7 9
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```
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And move on:
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```
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A B C D E F
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1 2 9 4 7 9
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```
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Now we broke out of the equality, but we need to re-sort the element `C`
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```
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A B D E F C
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1 2 4 7 9 9
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```
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And after shifting it rightwards, we check equality again, and find `C == F`, and thus
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call `Next` on `C`
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```
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A B D E F C
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1 2 4 7 9 -
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```
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At this point, `C` was exhausted, and is removed
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```
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A B D E F
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1 2 4 7 9
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```
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And we're done with this step.
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