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Computer Science

Andrew Stevens
Andrew Stevens
11,083 Points

How do you identify if a function has the same best-case or worse-case complexity?

for x in data:
    for y in data:
        print(x, y)

The above is a very simple example of O(N^2), but if I were asked to identify whether this code had the same best-case or worse-case complexity how would I go about calculating that?

1 Answer

This does have the same best/worst case complexity because it will always run x * y times.

That would not be true for something like this algorithm which searches for an element in a 2D array:

for x in data:
    for y in data[x]:
        if data[x][y] == "my element":
            print("found it")

The worst case complexity is x * y, the element is at the end so it has to search through the whole array The best case complexity is 1, the element is at the beginning so it can stop the search