using System;

using System.Collections.Generic;

​

/*Assumptions:

1) The String can be alphanuemric and it should be min of 1 and can go to any limit

2) The Input length has to be int

3) The input has to be valid int

4) The String count has to be greater than Input*/

namespace Program

{

    class Result

    {

        public string key;

        public int value;

        public Result(string key, int value)

        {

            this.key = key;

            this.value = value;

        }

    }

    class Program

    {

        public static void Main(string[] args)

        {

            try

            {

                Console.WriteLine("String Input");

                string strInput = Console.ReadLine();

                Console.WriteLine("Input Length:");

                //assuming that the input is int

                int strLength = int.Parse(Console.ReadLine());

                if (strInput.Length <= 1)

                    Console.WriteLine("No pattern exists");

                List<Result> list = getPatternsWithCount(strInput, strLength);

                for (int i = 0; i < list.Count; i++)

                    Console.WriteLine(list[i].key + ":" + list[i].value);

            }

            catch (Exception ex)

            {

                Console.WriteLine("Please enter Valid input and try again");

            }

        }

​

        //This method to get the list of pattern with count

        public static List<Result> getPatternsWithCount(string strInput, int strLength)

        {

            Dictionary<string, int> result = new Dictionary<string, int>();

            var list = new List<Result>();

            try

            {

                for (int i = 0; i <= strInput.Length - strLength; i++)

                {

                    string tempStr = strInput.Substring(i, strLength);

                    if (result.ContainsKey(tempStr))

                    {

                        int count = result.GetValueOrDefault(tempStr);

                        result[tempStr] = ++count;

                    }

                    else

                        result.Add(tempStr, 1);

                }

                foreach (KeyValuePair<string, int> entry in result)

                {

                    if (entry.Value > 1)

                        list.Add(new Result(entry.Key, entry.Value));

                }

            }

            catch (Exception ex) { }

​

            return list;

        }

    }

}

​