String Construction

FRom hackerrank

Amanda has a string of lowercase letters that she wants to copy to a new string. She can perform the following operations with the given costs. She can perform them any number of times to construct a new string :

• Append a character to the end of string  at a cost of  dollar.
• Choose any substring of  and append it to the end of  at no charge.

Given  strings , find and print the minimum cost of copying each  to  on a new line.

For example, given a string , it can be copied for  dollars. Start by copying ,  and  individually at a cost of  dollar per character. String  at this time. Copy  to the end of  at no cost to complete the copy.

Solution in C# -

class Solution {

    static int stringConstruction(string s) {

      string p = "";

        for(int i=0;i<s.Length;i++)

        {

            if(!p.Contains(s[i]))

            p = p+s[i];

        }

        return p.Length;

    }

    static void Main(string[] args) {

        TextWriter textWriter = new StreamWriter(@System.Environment.GetEnvironmentVariable("OUTPUT_PATH"), true);

       int q = Convert.ToInt32(Console.ReadLine());

        for (int qItr = 0; qItr < q; qItr++) {

            string s = Console.ReadLine();

            int result = stringConstruction(s);

            textWriter.WriteLine(result);

        }

        textWriter.Flush();

        textWriter.Close();

    }

}