#!/usr/bin/env python3
from decorators import counter, get_counter, trace


@counter
def fak(n):
    if type(n) is not int or n < 0:
        raise TypeError("Illegal type")
    if n == 0: 
        return 1
    return n * fak(n-1)

print("6! =", fak(6))
print("Anzahl Aufrufe:", get_counter(fak))

@trace
def fak(n): 
    if n == 0: 
        return 1
    return n * fak(n-1)

print(fak(4))