由于本节的原因，您获得了超出范围的错误:

You're getting an index out of bounds error because of this section:

for (i = 0; i < SIZE - 1; i++)
{
    if (numbers[i] > 0 && numbers[i] < SIZE)
    {
        x = Count[i];

请注意，当Count仅具有4的大小时，您正在遍历0到SIZE - 1(11).

Notice that you're iterating through 0 to SIZE - 1 (11) when Count only has a size of 4.

不过，您可以使用LINQ轻松完成此任务.

You can do this task pretty easily with LINQ though.

int[] numbers = new int[SIZE] { 5, 5, 5, 7, 7, 7, 9, 7, 9, 9, 9, 1 };

var count = numbers
    .GroupBy(e => e)
    .Where(e => e.Count() == 4)
    .Select(e => e.First());

因此它将数字按其值分组，然后我们将列表精简为仅包含4组，然后选择每个组中的第一个，并留下一个int s的集合.

So it groups the numbers by their value, we then refine the list to only include groups of 4, then select the first of each to be left with a collection of ints.

这是一个非基于Linq的解决方案，使用字典来存储数字计数.

Here is a non-LINQ based solution using a Dictionary to store the count of numbers.

int[] numbers = new int[SIZE] { 5, 5, 5, 7, 7, 7, 9, 7, 9, 9, 9, 1 };
var dictionary = new Dictionary<int, int>();
var numbersWithFour = new List<int>();

foreach (var number in numbers)
{
    if (dictionary.ContainsKey(number))
        dictionary[number]++;
    else
        dictionary.Add(number, 1);
}

foreach (var val in dictionary)
{
    if (val.Value == 4)
    {
        numbersWithFour.Add(val.Key);
    }
}

对程序进行一些修改，就可以得到一些结果.

With a little modification to your program you can get some results.

int[] numbers = new int[SIZE] { 5, 5, 5, 7, 7, 7, 9, 7, 9, 9, 9, 1 };
string[] letters = new string[SIZE] { "m", "m", "s", "m", "s", "s", "s", "m", "s", "s", "s", "s" };
int[] values = new int[SIZE] { 15, 22, 67, 45, 12, 21, 24, 51, 90, 60, 50, 44 };
string[] status = new string[SIZE] { "f", "m", "f", "a", "m", "f", "f", "f", "m", "f", "m", "f" };

// Set the size of Count to maximum value in numbers + 1
int[] Count = new int[9 + 1];
int x = 0;
int i = 0;

for (i = 0; i < SIZE - 1; i++)
{
    if (numbers[i] > 0 && numbers[i] < SIZE)
    {
        // Use value from numbers as the index for Count and increment the count
        Count[numbers[i]]++;
    }
}

for (i = 0; i < Count.Length; i++)
{
    // Check all values in Count, printing the ones where the count is 4
    if (Count[i] == 4)
        Console.WriteLine("{0}", i);
}

输出:

7
9