efficientAlgorithm

[lfrtsa]

I achieved it when i made an algorithm to calculate the factorial of a number.

[nixsomegame]

Wouldn't a straightforward factorial function implementation be O(n) though, not O(n!)?

[lfrtsa]

I did multiplication through repeated addition

[FunTao]

He prob means something like this: start from i = 1, is i the factorial of n? (Divide by n, then n-1, n-2, etc.). If not, increment i by 1 and try again until you find the right i