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Stepping backwards in for loop?
Alex Martellialeaxit at yahoo.com
Sat Apr 14 10:30:36 EDT 2001
"Gustaf Liljegren" <gustafl at algonet.se> wrote in messagenews:Xns9083A46CB3B93gustaflalgonetse at 194.213.69.152...> Can't figure out how to step backwards, character by character in astring.> I was looking for a loop countruct with a counter to handle this, but the> for loop in Python doesn't let me step backwards. What is the alternative?You have several alternatives, such as:thestr = 'ciao'for x in range(len(thestr), 0, -1): print thestr[x-1],printfor x in range(len(thestr)): print thestr[-x-1],printaulist = list(thestr)aulist.reverse()for c in aulist: print c,printclass Reverse: def __init__(self, seq): self.seq = seq def __getitem__(self, index): return self.seq[-index-1]for c in Reverse('ciao'): print c,printEach of these snippets will print 'o a i c'.Alex
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