Big O (Time Complexity)

Big O Notation	Name	Example
O(1)	Constant	Choosing one item by index from an array, no matter how long the array it will be the same.
O(log n)	Logarithmic	Binary search, because every time a comparison is made it is more likely that the search is complete. The search area is halved each time.
O(n)	Linear	Summing all elements in an array, because each element needs to be checked once so it will increase linearly with the size of the array (n).
O(n log n)	Linearithmic
O(n^2)	Quadratic
O(n^3)	Cubic
O(2^n)	Exponential
O(n!)	Factorial

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