SRM489 - div2 - level one

srm489_div2_level1.py

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

"""SRM489 - div2 - level one

Little Teddy and Little Tracy are now learning how to speak words. 
Their mother, of course, doesn't want them to speak bad words. 
According to her definition, a word W is bad if at least one of 
the following conditions hold (see the notes section for definitions):

    * W contains the string badPrefix as a prefix.
    * W contains the string badSuffix as a suffix.
    * W contains the string badSubstring as a contiguous substring 
      that is neither a prefix nor a suffix of W.

Definition:
    Class: BadVocabulary
    Method: count
    Parameters: String, String, String, String[]
    Returns: int
    Method signature: int count(String badPrefix, String badSuffix, 
            String badSubstring, String[] vocabulary)

Notes
    - A prefix of a string is obtained by removing zero or more 
      contiguous characters from the end of the string.
    - A suffix of a string is obtained by removing zero or more 
      contiguous characters from the beginning of the string.
"""

class BadVocabulary(object):
    """Time Travelling Cellar

    Constraints:
        - badPrefix, badSuffix, and badSubstring will each contain 
          between 1 and 50 characters, inclusive.
        - vocabulary will contain between 1 and 50 elements, inclusive.
        - Each element vocabulary will contain between 1 and 50 characters, 
          inclusive.
        - Each character of badPrefix, badSuffix, and badSubstring 
          will be between 'a' and 'z', inclusive.
        - Each character in vocabulary will be between 'a' and 'z', inclusive.
        - All elements of vocabulary will be distinct.

    >>> vocabluraly = BadVocabulary()
    >>> print vocabluraly.count("bug", "bug", "bug", 
    ...     ["buggy", "debugger", "debug", ])
    3
    >>> print vocabluraly.count("a", "b", "c", 
    ...     ["a", "b", "tco", ])
    3
    >>> print vocabluraly.count("cut", "sore", "scar", 
    ...     ["scary", "oscar", ])
    0
    >>> print vocabluraly.count("bar", "else", "foo", 
    ...     ["foofoofoo", "foobar", "elsewhere", ])
    1
    >>> print vocabluraly.count("pre", "s", "all", 
    ...     ["all", "coders", "be", "prepared", "for", "the", "challenge", "phase", ])
    3
    """

    def __init__(self):
        pass

    def count(self, badPrefix, badSuffix, badSubstring, vocabulary):
        c = 0
        for word in vocabulary:
            if word[:len(badPrefix)] == badPrefix \
                    or word[-(len(badSuffix)):] == badSuffix \
                    or badSubstring in word[1:-1]:
                c += 1
        return c

if __name__ == '__main__':
    import doctest
    doctest.testmod()