using System;

public class Program

{

    public static void Main()

    {

        string text = "aslijfowjlfaksdsfgldsjfrcieasdsdgsadas";

        //string text = "arciea";

        string pattern = "eric";

        if (isAnagramSubstring(pattern, text)) {

            Console.WriteLine("Hello World");

        }

    }

​

    public static bool equals(int[] pattern, int[] text) {      

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

            if (pattern[i] != text[i])  {

                return false;   

            }

        }

        return true;

    }

    public static bool isAnagramSubstring(string pattern, string text) {

        int[] textMap = new int[256];

        int[] patternMap = new int[256];

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

            textMap[text[i]]++;

            patternMap[pattern[i]]++;

        }

        int j = pattern.Length;

        while(j < text.Length) {

            if (equals(patternMap, textMap)) {

                return true;

            }

            textMap[text[j - pattern.Length]]--;

            textMap[text[j]]++;

            j++;

        }

        // need to check last window

        if (equals(patternMap, textMap)) {

            return true;

        }

        return false;

    }

}