python版本 取序列中的topK最大值

创建小根堆, 使用python内部的模块 heapq

import heapq
import random

class TopK:

    def __init__(self, li, k):
        self.minheap = []
        self.capacity = k
        self.li = li

    def push(self, val):
        if len(self.minheap) >= self.capacity:
            # 大于等于想要的元素个数
            min_val = self.minheap[0]
            if val < min_val:  
                # 新元素比最小的还小, 直接忽略
                pass
            else:
                # 比最小的大, name进行替换, 先取出最小的, 然后添加新元素, 内部会重新调整小堆根
                heapq.heapreplace(self.minheap, val)  
        else:
            # 个数小于k, 直接添加
            heapq.heappush(self.minheap, val) 
            
    def get_topk(self):
        for val in self.li:
            self.push(val)
        return self.minheap


def test():
    li = list(range(1000))  
    random.shuffle(li)
    obj = TopK(li, 10)
    print(obj.get_topk())  

if __name__ == '__main__':
    test()

结果:

[990, 992, 991, 993, 995, 994, 996, 997, 998, 999]