using System;

//Firstly i'd like to say that this is my first time writing a program in C#

//so i appolgize if I didnt quite use classes properly or made some other 

//language specific error. I typically code in C++ but I am a fast learner

//and caught on to c# with relative ease.

​

namespace liveSwitch{

​

    class Pattern{

        public string pattern;

        public int occurrences;

​

        public Pattern(string str, int count){

            pattern = str;

            occurrences = count;

        }

    }

​

    /*

        Approach: Iterate through the string twice, comparing every substring of length 

        patternLength with every other substring of length PatternLength in the string.

​

    */

    class patternRecognition{

        //patterns takes input and patern length and returns an array of Pattern objects

        //containing the pattern and number of occurances

        public Pattern[] patterns(string input, int patternLength){

            int len = input.Length;

            string[] subStrings = new string[len];

            int[] count = new int[len];

            int occurrences = 0;

            int currentEntry = 0;

            bool newSubstring = true;

            for(int i = 0; i <= len - patternLength; i++){

                occurrences = 0;

                for(int j = i; j <= len - patternLength; j++){

                    if(input.Substring(i, patternLength) == input.Substring(j, patternLength)){

                        occurrences++;

                    }

                }

                //if the pattern occurs more than once

                if(occurrences > 1){

                    newSubstring = true;

                    for(int k = 0; k < currentEntry; k++){//check if it has already been counted

                        if(subStrings[k] == input.Substring(i, patternLength)){

                            newSubstring = false;

                        }

                    }//if not add it to the arrays

                    if(newSubstring){

                        subStrings[currentEntry] = input.Substring(i, patternLength);

                        count[currentEntry] = occurrences;

                        currentEntry++;

                    }

                }

            }

            //create a new array to hold patern objects using the first two arrays

            //unless there are no duplicate patterns, then return an empty array.

            if(currentEntry!= 0){

                Pattern[] patterns = new Pattern[currentEntry];

                for(int i = 0; i < currentEntry; i++){

                    patterns[i] = new Pattern(subStrings[i], count[i]);

                }

                return patterns;

            }else{

                Pattern[] patterns = new Pattern[currentEntry];

                return patterns;

            }

        }

    }

    class liveSwitch{

​

        static void Main(string[] args){

            patternRecognition p = new patternRecognition();

            Pattern[] pArr = p.patterns("zf3kabxcde224lkzf3mabxc51+crsdtzf3nab=", 3);

            foreach(Pattern pattern in pArr){

                Console.WriteLine(pattern.pattern +": " + pattern.occurrences);

            }

        }

​

    }

}

​

​

​