264. Ugly Number II.py 文件源码

def nthUglyNumber(self, n):
        """
        :type n: int
        :rtype: int
        """
        l=[1]
        primes=[2,3,5]
        heapq.heapify(l)
        set1=set(l)
        n-=1
        while n>0:
            z=heapq.heappop(l)
            n-=1
            for i in primes:
                if z*i not in set1:
                    heapq.heappush(l, z*i)
                    set1.add(z*i)
        return heapq.heappop(l)