for ck in sorted(range(min(self.p, self.q)+1), reverse = True):
if self.p % ck == 0 and self.q % ck == 0:
self.p = self.p / ck
self.q = self.q / ck
break
return '%s/%s' % (self.p, self.q)
生成数列：
def __init__(self, num):
if num == 1:
self.fib = [0]
else:
self.fib = [0,1]
while num != 2 :
self.fib.append(self.fib[-2]+self.fib[-1])
num = num - 1
