如何用C#找出数组中只出现了一次的数字

Dictionary<int, int> input= new Dictionary<int, int>();
for(int i = 0; i < 10; i++)
{
    Console.Write($"请输入第{i+1}个数：");
    int temp = Convert.ToInt32(Console.ReadLine());
    // 如果存在要添加的
    if (input.ContainsKey(temp))
    {
        // 记录输入次数+1
        input[temp]++;
    }
    else
    {
        // 不存在计数1次
        input.Add(temp, 1);
    }
}

Console.WriteLine($"出现过一次的有：");
foreach(var one in input)
{
    if(one.Value == 1)
    {
        Console.WriteLine(one.Key);
    }
}

// 记录输入
List<int> numbers = new List<int> { };
// 记录重复的
List<int> notthis = new List<int> { };
for (int i = 0; i < 10; i++)
{
    Console.Write($"请输入第{i + 1}个数：");
    int temp = Convert.ToInt32(Console.ReadLine());
    if (numbers.Contains(temp))
    {
        notthis.Add(temp);
    }
    numbers.Add(temp);
}
Console.WriteLine($"出现过一次的有：");
foreach (int one in numbers)
{
    if (!notthis.Contains(one))
    {
        Console.WriteLine(one);
    }
}

List<int> haveone = numbers.Except(notthis).ToList();
Console.WriteLine($"出现过一次的有：{string.Join(",", haveone)}");

List<int> numbers = new List<int> { };
for (int i = 0; i < 10; i++)
{
    Console.Write($"请输入第{i + 1}个数：");
    int temp = Convert.ToInt32(Console.ReadLine());
    numbers.Add(temp);
}

var linquse = numbers.GroupBy(x => x)
    .Where(g => g.Count() == 1)
    .Select(s => s.Key);
Console.WriteLine($"出现过一次的有：{string.Join(",", linquse)}");

        public static int Search(int[] arrs)
        {            
            int len = arrs.Length;
            int max = 0;  //出现最多的次数
            int num = 0;  //当前的数字
            
            List<int> temps = new List<int>(); //a
            for (int i = 0; i < len; i++)
            {
                if (temps.Contains(arrs[i])) continue;      //排除之前参与过的数字        
                int count = 0;
                for (int j = 0; j < len; j++)
                {
                    if (arrs[i] == arrs[j])
                    {
                        count++;
                    }
                }
                if (count > max)
                {
                    max = count;
                    num = arrs[i];
                }
                temps.Add(arrs[i]); //a
            }
            return num;
        }