Exponential

Exponential algorithms are those that grow at a rate of 2^n. This means that for each additional input, the algorithm will take twice as long to run. The following function is an example of an exponential algorithm:

def exponential(n):
    if n == 0:
        return 1
    return exponential(n - 1) + exponential(n - 1)

As you can see, the algorithm's runtime grows exponentially. For each additional input, the algorithm will take twice as long to run.