How to get distinct characters?

Question

I have a code like

string code = \"AABBDDCCRRFF\";

In this code, I want to retrieve only distinct characters

The Output should be l

Answer 1

To get all distinct characters I have used ascii array. steps 1. Added ascii array of size 256, becuase max char ascii value is 255 step 2. increment each ascii to the location of particular alphabet's ascii value

please refer below code to understand.

public static class StringManipulation
{
  public static string UniqueChars(this string astrInputString)
  {
       astrInputString = astrInputString.ToLower();
    int[] arrAscii = new int[256];
    string lstrFinalOutput = string.Empty;
    for (int i = 0; i < astrInputString.Length; i++)
    {
        arrAscii[Convert.ToInt32(astrInputString[i])]++;
    }

    for (int i = 0; i < astrInputString.Length; i++)
    {
        if (arrAscii[Convert.ToInt32(astrInputString[i])] == 1)
            lstrFinalOutput = lstrFinalOutput + astrInputString[i];
    }
    return lstrFinalOutput;
  }
}
class Program
{
  static void Main(string[] args)
  {
    string input = "AAssjjkkLLlx";
    Console.WriteLine("Unique Charcters in string " + input.UniqueChars());

  }
}

Click to Download this Code https://github.com/SiddharthBhamare/StringManipulation/blob/master/StringManipulation/Program.cs