Can you please explain the output of this code?

Question

def rec(n):
n %= 5
if n <= 1:
return n
else:
return rec(n-1) + rec(n-2)
print(rec(9))

Answer 1

I will try to explain and I made the code different so you can check the results:
def rec(n):
n %= 5
if n <= 1:
return n
else:
return rec(n-1) + rec(n-2)
print(rec(0)) # upper return so it will be 0
print(rec(1)) # upper return so it will be 1
print(rec(2)) # lower return so it will be rec(1) + rec(0) == 1
print(rec(3)) # lower return so it will be rec(2) + rec(1) == 2
print(rec(4)) # lower return so it will be rec(3) + rec(2) == 3
# 9 % 5 == 4 so rec(9) == rec(4)

Answer 2

It's called recursive function.
When function call itself recursion happen.

Check out this video for better understanding:https://youtu.be/XkL3SUioNvo

Answer 3

_ i in range(0, 20,_ ):
print(-)
fill this blanks