using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp1
{
    class Program
    {

        static void Main(string[] args)
        {
            var arr = new int[] { 4, 1, 1, 4, 2, 3, 4, 4, 1, 2, 4, 9, 3 };
            var arr2 = new int[15];
            for (int i = 0; i < 15; i++)
            {
                for (int j = 0; j < arr.Length; j++)
                {
                    if(i==arr[j])
                    {
                        arr2[i]++;
                    }
                }
            }
            int temp;
            for (int i = 0; i <arr2.Length-1; i++)
            {
                for (int j = 0; j <arr2.Length-i-1; j++)
                {
                    if(arr2[j]<arr2[j+1])
                    {
                        temp = arr2[j];
                        arr2[j] = arr2[j + 1];
                        arr2[j + 1] = temp;
                    }
                }
            }
            Console.WriteLine(arr2[0]);
        }
    }
}