HackerRank: Sherlock And Anagram (VI)

March 27, 2016

 Julia was surprised to have a workout on this moderate difficult string problem from 9:00am - 4:00pm. She did some code study, and then, read so many codes from Microsoft, box, and saleforce, Amazon, and then, she read linkin profile, and blogs. She is getting connected to all other programmers in the world. HackerRank is young, all the coders are in charge of business this world, right now! No complaint.

 Just learn one good code  a time. Pay attention to some details. Follow up with a revisit once a while. Julia, you will make your programmer life easy, just relax, and see how people are creative to solve problems. You should do so, just copy the idea. Make sure that think by yourself first, do not be a copycat.

 This code is her favorite. She is still learning, never use SortedDictionary before,


 code reference:
https://www.hackerrank.com/Relentless

http://anothercasualcoder.blogspot.ca/#!

 Julia is too busy to work on coding, so she chooses on easy to moderate questions. She waited until 7 - 10 string questions, and then, finally, she worked on her first moderate question on HackerRank after 1 - 2 months. But, she likes to read other people's code, and then, she just needs ideas to solve problems.

 Here is the code gist:

https://gist.github.com/jianminchen/22f8e0de115cf656995e

/*
 Julia likes to talk about design of the function, through debugging, she knows a few things:

  For string "abba", 
  First, go over string with length 1, 
  then, SortedDictionary - key 'a', 'b', values are 2, 2
  then, Hashtable htPairs - key: a2, value: 

  then, go over string with length 2, 
  then, SortedDictionary - key 'a', value 1; key 'b', value '1'

  "abba" go through a loop, to get substring with length 2, in the order:
    ^  ->
     |
    "ab", 
    "bb", 
    "ba"
1.   string "ab", , key "a1b1",   htPairs["a1b1"] = 1
2.  string "bb", key "b2",          htPairs["b2"] = 1
3.  string "ba",            hashTable contains the key, so the value htPairs["a1b1] = 2
  Hashtable key "a1b1", sortedDictionary, value 2

*/
 static BigInteger UnorderedAnagrams(string str)
    {
        Hashtable htPairs = new Hashtable();

        for (int len = 1; len <= str.Length; len++)
        {
            for (int i = 0; i + len <= str.Length; i++)
            {
                SortedDictionary<char, int> anagram = new SortedDictionary<char, int>();
                for (int j = i; j < i + len; j++)
                {
                    if (anagram.ContainsKey(str[j]))
                    {
                        anagram[str[j]] = (int)anagram[str[j]] + 1;
                    }
                    else
                    {
                        anagram.Add(str[j], 1);
                    }
                }

                string finalKey = "";
                foreach (char key in anagram.Keys)
                {
                    finalKey += key.ToString() + ((int)anagram[key]).ToString();
                }

                if (!htPairs.ContainsKey(finalKey))
                {
                    htPairs.Add(finalKey, 1);
                }
                else
                {
                    htPairs[finalKey] = (int)htPairs[finalKey] + 1;
                }
            }
        }

        BigInteger finalResult = 0;
        foreach (string k in htPairs.Keys)
        {
            finalResult += Combinatorial((int)htPairs[k], 2);
        }

        return finalResult;
    }
Blogs:
http://juliachencoding.blogspot.ca/2016/03/hackerrank-string-sherlock-and-anagrams.html