Write a program in C# count the duplicate Numbers?

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ConsoleApplication1

{
class Program

{
static void Main(string[] args)

{
int[] array = { 10,15,6,6,5, 10, 2, 2, 3, 4, 5, 5, 6, 7, 8, 9, 11, 12, 12 };

int count = 1;

for (int i = 0; i < array.Length; i++)

{
for (int j = i; j < array.Length - 1; j++)

{
if (array[j] == array[j + 1])

count = count + 1;

} Console.WriteLine("\t\n " + " Number of Duplecate value:" + " " + count);

Console.ReadLine();

}

}

}

}

Output: