Codeforces Round #253 Tutorial
443A - Anton and Letters
Simple and easy, solved by two lines of python code.
ls = filter(lambda y: y, map(lambda x: x.strip(), raw_input()[1:-1].split(",")))
print len(set(ls))
443B - Kolya and Tandem Repeat
Brute force. Just enumerate the beginning and the end of the substring, and …
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