How to calculate big-theta
Can some one provide me a real time example for how to calculate big theta. Is big theta some thing like average case, (min-max)/2? I mean (minimum time – big O)/2 Please correct me if I am wrong, thanks
big-o
Is log(n!) = Θ(n·log(n))?
Remember that You can get the upper bound by And you can get the lower bound by doing a similar thing after throwing away the first half of the sum:
O(n log n) vs O(n) — practical differences in time complexity
The main purpose of the Big-O notation is to let you do the estimates like the ones you did in your post, and decide for yourself if spending your effort coding a typically more advanced algorithm is worth the additional CPU cycles that you are going to buy with that code improvement. Depending on the … Read more
Big O, how do you calculate/approximate it?
I’ll do my best to explain it here on simple terms, but be warned that this topic takes my students a couple of months to finally grasp. You can find more information on the Chapter 2 of the Data Structures and Algorithms in Java book. There is no mechanical procedure that can be used to get the BigOh. As … Read more
Example of O(n!)?
There you go. This is probably the most trivial example of a function that runs in O(n!) time (where n is the argument to the function):
Determining complexity for recursive functions (Big O notation)
The time complexity, in Big O notation, for each function: This function is being called recursively n times before reaching the base case so its O(n), often called linear. This function is called n-5 for each time, so we deduct five from n before calling the function, but n-5 is also O(n). (Actually called order of n/5 times. … Read more
Time complexity of a Priority Queue in C++
If you have an array of size n and you want to build a heap from all items at once, Floyd’s algorithm can do it with O(n) complexity. See Building a heap. This corresponds to the std::priority_queue constructors that accept a container parameter. If you have an empty priority queue to which you want to add n items, one at a time, … Read more
Understanding Time complexity calculation for Dijkstra Algorithm
Dijkstra’s shortest path algorithm is O(ElogV) where: V is the number of vertices E is the total number of edges Your analysis is correct, but your symbols have different meanings! You say the algorithm is O(VElogV) where: V is the number of vertices E is the maximum number of edges attached to a single node. Let’s rename your E to N. So one analysis says O(ElogV) and another … Read more
What does O(log n) mean exactly?
The most common attributes of logarithmic running-time function are that: the choice of the next element on which to perform some action is one of several possibilities, and only one will need to be chosen. or the elements on which the action is performed are digits of n This is why, for example, looking up … Read more
what does O(N) mean [duplicate]
The comment was referring to the Big-O Notation. Briefly: O(1) means in constant time – independent of the number of items. O(N) means in proportion to the number of items. O(log N) means a time proportional to log(N) Basically any ‘O’ notation means an operation will take time up to a maximum of k*f(N)where: k is a … Read more