# 재귀함수
def func(n):
    func_number = 0
    if n==0:
        return 1
    else:
        return n* func(n-1)   

number = 5
result = func(number)
print(f"func({number})= {result}")


# while 반복함수로 변경 
def iter_fun(n):
    f=1
    while(n>0):
        f=f*n
        n=n-1
    return f

number_1 = 5
result_1 = iter_fun(number_1)
print(f"iter_fun({number_1})= {result_1}")

# for 반복함수로 변경 
def iter2_fun(n):
    f=1
    for i in range(n): 
        f=f*n
        n=n-1
    return f

number_2 = 5
result_2 = iter_fun(number_2)
print(f"iter2_fun({number_2})= {result_2}")