Why is the time complexity for insertion of a string into an unordered_map, constant on average?
Question
If we have a string of length n, then shouldn't the time for inserting it into an unordered_map (C++) be O(n)? But in the cplusplus.com website:
The following is written:
So, what is the correct time complexity? Thank you!
1 answers
solution1
7 ACCPTED 2021-01-08 09:08:08
In this context, constant time refers to the number of elements in the map, not anything about those elements.
If you have a string of size n , and insert it into a map of size m , O(n) insertion is constant in m .
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