http://programmingpraxis.com/2010/11/23/string-subsets/ import operator import collections def is_str_subset(sub, base): D = collections.defaultdict(lambda : 0) for c in list(base): D[c] += 1 for c in list(sub): D[c] -= 1 if D[c] < 0: retu…

http://programmingpraxis.com/2010/12/03/maximum-sum-subsequence/ def max_subseq(xs): prev_max, cur_max = 0,0 for x in xs: tmp = x+prev_max if prev_max >= 0 else x cur_max = max(tmp, cur_max) prev_max = tmp return cur_max L=[31, -41, 59, 26…

http://programmingpraxis.com/2010/11/30/form-letters/ import re def from_letters(message, seq): def repl(m): i = int(m.group(2)) return m.group(1)+seq[i] return re.sub(r'([^\$])\$(\d+)', repl, message) S = """ Welcome back, $1! We hope tha…