#!/usr/bin/env python
# -*- coding: utf-8 -*-


def damm_algorithm(n):
    matrix = [[0, 3, 1, 7, 5, 9, 8, 6, 4, 2], [7, 0, 9, 2, 1, 5, 4, 8, 6, 3],
              [4, 2, 0, 6, 8, 7, 1, 3, 5, 9], [1, 7, 5, 0, 9, 8, 3, 4, 2, 6],
              [6, 1, 2, 3, 0, 4, 5, 9, 7, 8], [3, 6, 7, 4, 2, 0, 9, 5, 8, 1],
              [5, 8, 6, 9, 7, 2, 0, 1, 3, 4], [8, 9, 4, 5, 3, 6, 2, 0, 1, 7],
              [9, 4, 3, 8, 6, 1, 7, 2, 0, 5], [2, 5, 8, 1, 4, 3, 6, 7, 9, 0]]

    checksum = 0
    for digit in str(n):
        checksum = matrix[checksum][int(digit)]

    return checksum == 0


# testing
n = 5724
print(damm_algorithm(n))  # should print True

n = 5727
print(damm_algorithm(n))  # should print False