def trim(s): start = 0; end = len(s); while s[start:start+1] == ' ' and start < end: start += 1 while s[end-1:end] == ' ' and start < end: end -= 1 if start == end: return '' else: return s[start:end]
def trim(s): start = 0; end = len(s); while s[start:start+1] == ' ' and start < end: start += 1 while s[end-1:end] == ' ' and start < end: end -= 1 if start == end: return '' else: return s[start:end]