binary = lambda i, math = __import__('math'): ''.join([str(int((i >> x) & 1L
)) for x in range(int(math.log(i) / math.log(2)) + 1, -1, -1)]).lstrip('0')

binary = lambda i, c = (lambda i, c: i and (c(i >> 1, c) + str(i & 1)) or ''): c(i, c)