using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(anagramChecker("test", "test"));

        Console.WriteLine(anagramChecker("test", "tests"));

        Console.WriteLine(anagramChecker("test", "tess"));

        Console.WriteLine(anagramChecker("test", "stet"));

        Console.WriteLine(anagramChecker("test", "tes"));

        Console.WriteLine(anagramChecker("", ""));

    }

    private static bool anagramChecker(string s1, string s2)

    {

        if (String.IsNullOrEmpty(s1) || String.IsNullOrEmpty(s2))

            return false;

        if (s1.Equals(s2))

            return true;

        if (s1.Length != s2.Length)

            return false;

        Dictionary<char, int> s1Chars = getCharDictionary(s1);      

        Dictionary<char, int> s2Chars = getCharDictionary(s2);

​

        char currentChar;

        for (int i = 0; i<s1Chars.Keys.Count; i++)

        {

            currentChar = s1Chars.ElementAt(i).Key;

            if (!containsChar(currentChar, s1Chars[currentChar], s2Chars))

                return false;

        }

        return true;

    }

    private static Dictionary<char, int> getCharDictionary(string val)

    {

        Dictionary<char, int> temp = new Dictionary<char, int>();

        char[] chars = val.ToCharArray();

        int numFound;

        char currentChar;

        // Can be optimized ? 

        // while chars.Length > 0

        // int countChar(ref chars, currentChar)

        // will remove currentChar from chars

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

        {

            currentChar = chars[i];

            if (temp.ContainsKey(currentChar))

                continue;// No need to check again

            numFound = 1;

            for (int y = i+1; y < chars.Length; y++)

            {

                if (chars[y].Equals(currentChar))

                    numFound++;

            }

            temp.Add(currentChar, numFound);

        }

        return temp;

    }

    private static bool containsChar(char val, int numTimes, Dictionary<char, int> chars)

    {

        return (chars.ContainsKey((val)) && chars[val] == numTimes);

    }

}