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Complexity

There are different measurements of the speed of any given algorithm. Given an input size of N, they can be described as follows:

Name Speed Description Formula
exponential time slow takes an amount of time proportional to a constant raised to the Nth power K^N
polynomial time fast takes an amount of time proportional to N raised to some constant power N^K
linear time faster takes an amount of time directly proportional to N K * N
logarithmic time much faster takes an amount of time proportional to the logarithm of N log(N)
constant time fastest takes a fixed amount of time, no matter how large the input is K