28 lines
1.4 KiB
Markdown
28 lines
1.4 KiB
Markdown
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The first basic data-structure everybody should learn is the singly linked list.
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In a singly linked list you save your data in nodes, a combination of data and a pointer
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to the next node. To add nodes you simply allocate them and rewire the pointers,
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such that it appears in the right spot in the list.
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To remove an element you have to rewire the previous and next node, such that their
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pointers point to each other, and then free the memory.
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The idea behind this data-structures is, that you can add and remove elements easily
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from the end, front and middle of the list. And because you just allocate more memory,
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the list can grow dynamically.
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The problem is to get to the elements.
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Because they are allocated on the heap the elements are all over the place and can only
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be found via the pointers. So, when you want to get to the middle, you have to traverse
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the linked list.
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Another downside of singly linked list is, that you can't go backwards.
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That is were the doubly linked list comes in, but more on that later.
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The last disadvantage is, when you want to process lot's of data in a short amount of time,
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you are often limited by cache misses. And linked list in general are terrible for that kind
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of work, because most elements aren't in the same cache line.
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Your task will be to implement the functions for add, insert_after, remove and get.
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It is often helpful to draw the operations you want to do on paper or
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look at some pictures.
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