def digitDegree(n):
    degree = 0
    num = str(n)
    while len(num) > 1:
        new = 0
        for i in range(len(num)):
            new += int(num[i])
        num = str(new)
        degree +=1
    return degree

digit = 99
print(digitDegree(digit))

'''
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.
'''