'''
Write a method to count the number of 2s that appear in all the numbers between 0 and n (inclusive).

Example:
    Input: 25
    Output: 9 (2, 12, 20, 21, 22, 23, 24, and 25. Note that 22 counts for two 2s.)

Hints: 573, 612, 641
'''


def countof2s(s):
    pass

if __name__ == '__main__':
    assert countof2s('') ==
    assert countof2s('') ==
    assert countof2s('') ==
    assert countof2s('') ==
    assert countof2s('') ==
