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2answers
509 views

### Difference between O(N^2) and Θ(N^2) [duplicate]

What is the difference between O(N^2) and Θ(N^2)? I know that O is the upper bound and Θ is tight bound. Could someone explain me this concept with an example.
1answer
844 views

### Notation for the average time complexity of an algorithm

What notation do you use for the average time complexity of an algorithm? It occurs to me that the proper way would be to use big-theta to refer to a set of results (even when a specific try may ...
5answers
679 views

### Programmaticaly finding the Landau notation (Big O or Theta notation) of an algorithm?

I'm used to search for the Landau (Big O, Theta...) notation of my algorithms by hand to make sure they are as optimized as they can be, but when the functions are getting really big and complex, it's ...
3answers
1k views

### Please explain the statement that the function an+b belongs to O(n^2) and Θ(n)?

Let's say I have a linear function f(n)= an+b, what is the best way to prove that this function belongs to O(n2) and Θ(n)? I do not need mathematical rigor here. I need a programmers answer. Some ...
5answers
4k views

### Theta notation on constant time. Why we use the 1?

In asymptotic notation when it is stated that if the problem size is small enough (e.g. n<c for some constant c) the solution takes constant time and is writen as Theta(1). Why we write 1 inside ...
2answers
4k views

### Why is Big O taught instead of Big Theta?

Big O notation provides an upper bound to a function whereas Big Theta provides a tight bound. However I find that Big O notation is typically (and informally) taught and used when they really mean ...