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
analysis
The meaning of the question is: given an array, find the sum of the numbers with a frequency of 1.
The idea is also very straightforward. Use a dictionary to count the frequencies, and then just sum the numbers with a frequency of 1 in the alignment.
Code
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