import re for s in ("100", "100.000", "100.01a", "100.01000a", ".10*100.00", "2.020") : print s + " -> " + str(re.sub('(\d\.|\.\d*[1-9])0+(?!\d)',r'\1',s))
Standard input is empty
100 -> 100 100.000 -> 100. 100.01a -> 100.01a 100.01000a -> 100.01a .10*100.00 -> .1*100. 2.020 -> 2.02