A handy table with common function structures and their algorithmic complexities:

Big O notation	Name	Sample
O(1)	Constant	Dictionary or object access
O(log 1)	Logarithmic	Binary search
O(n)	Linear	Loop
O(n log n)	Linerithmic	Loop * binary search
O(n^2)	Quadratic	Two nested loops
O(n^k)	Polinomial	k nested loops
O(2^n)	Exponential	Recursion
O(n!)	Factorial	Recursion within a loop

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