1748. Sum of unique elements

 

Give you an array of integers nums . The only elements in an array are those that only appear Elements that happen to happen once . Please return nums Sum of unique elements in .

public static int SumOfUnique(int[] nums)
        {
            Dictionary<int, int> dict = new Dictionary<int, int>();
            foreach (var item in nums)
            {
                if (dict.ContainsKey(item))// Is there in the dictionary item This key 
                {
                    dict[item]++;// If so, add one to the value corresponding to this key 
                }
                else
                {
                    dict.Add(item, 1);// The value corresponding to adding this key is 1
                }
            }

            int sum = 0;
            foreach (var item in dict)
            {
                if (item.Value == 1)// The median value of this set of key values that you cycle to is equal to 1 Words 
                {
                    sum += item.Key;// Add keys together 
                }
            }
            return sum;

        }