Let's define digit degree of some positive integer as the number of times we need to replace this number with the sum of its digits until we get to a one digit number.

Given an integer, find its digit degree.

Example

• For n = 5, the output should be
  digitDegree(n) = 0;
• For n = 100, the output should be
  digitDegree(n) = 1.
  1 + 0 + 0 = 1.
• For n = 91, the output should be
  digitDegree(n) = 2.
  9 + 1 = 10 -> 1 + 0 = 1.

我的解答：

def digitDegree(n):

    s = 0

    count = 1

    if len(str(n)) == 1:

        return 0

    for i in str(n):

        s += int(i)

    if len(str(s)) == 1:

        return 1

    while s >= 10:

        c = 0

        for i in str(s):

            c = c + int(i)

        s = c

    return count + 1

def digitDegree(n):

    d=0

    while n>=10:

        n=sum([int(i) for i in str(n)])

        d+=1

    return d