leetcode1342

Posted 2021-03-12 AsenYang

 1 class Solution:
 2     def minSetSize(self, arr: ‘List[int]‘) -> int:
 3         m = len(arr)
 4         dic = {}
 5         for i in range(m):
 6             if arr[i] in dic:
 7                 dic[arr[i]] += 1
 8             else:
 9                 dic[arr[i]] = 1
10         l = sorted(dic.items(),key=lambda d:(-d[1]))
11         count,target,size = 0,m // 2,0
12         for x in range(len(l)):
13             if count >= target:
14                 return size
15             else:
16                 size += 1
17                 count += l[x][1]
18         return size

算法思想：贪心。

按照出现频率从高到低排序，优先将出现次数多的数字加入到被去除的集合中。