Intermediate · Functions · 114 of 264
Digital root
Add up the digits of a number, then the digits of the result, and so on until one digit is left. Print that digit.
Input: a positive whole number. Output: its digital root.
Examples
Input
942
Output
6
Input
5
Output
5
Input
99999999999
Output
9
One more test checks other inputs when you press Check.
Stuck? The idea behind functions
A function, made with def, gives a name to a piece of code, so it can be used again: its parameters are the values it is given, return hands an answer back.
A function that returns lets the caller decide what to do with the answer: print it, compare it, use it in a sum.
def is_even(n):
return n % 2 == 0
print(is_even(4))
print(is_even(7))Watch for: print inside a function is not return: the caller gets None. And the code after return in the same block never runs.