使用heapq获取最大N项和最小N项
>>> import heapq >>> nums = [1, 8, 2, 23, 7, -4, 18, 23, 42, 37, 2] >>> print heapq.nlargest(3, nums) [42, 37, 23] >>> print heapq.nsmallest(3, nums) [-4, 1, 2]
