How to create a collection with O (1) complexity

Question

I would like to create a data structure or collection that will have O (1) complexity when adding, deleting and evaluating no. elements. How should i start?

I thought of a solution: I will use a Hashtable and for each key / value pair inserted, I will have only one hash code, that is: my hash code algorithm will generate a unique hash value each time, so every time, the index in which stores the value will be unique (i.e. no collisions).

Will it give me O (1) complexity?

Answer 1

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Answer 2

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Answer 3

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Answer 4

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Answer 5

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Answer 7

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