Description

You are given an integer array nums. The unique elements of an array are the elements that appear exactly once in the array.

Return the sum of all the unique elements of nums.

Example 1:

Input: nums = [1,2,3,2]
Output: 4
Explanation: The unique elements are [1,3], and the sum is 4.

Example 2:

Input: nums = [1,1,1,1,1]
Output: 0
Explanation: There are no unique elements, and the sum is 0.

Example 3:

Input: nums = [1,2,3,4,5]
Output: 15
Explanation: The unique elements are [1,2,3,4,5], and the sum is 15.

Constraints:

• 1 <= nums.length <= 100
• 1 <= nums[i] <= 100

分析

题目的意思是：给定数组，求出频率为1的数字的求和。
思路也很直接，用字典统计频率，然后对齐中频率为1的数求和就行了。

代码

class Solution:
    def sumOfUnique(self, nums: List[int]) -> int:
        d=defaultdict(int)
        for num in nums:
            d[num]+=1
        res=0
        for k,v in d.items():
            if(v==1):
                res+=k
        return res