Problem:
Score : 200 points

Problem Statement

You are given a string S of length N consisting of lowercase English letters, and an integer K.
Print the string obtained by replacing every character in S that differs from the K-th character of S, with *.

Constraints

1 \leq K \leq N\leq 10

S is a string of length N consisting of lowercase English letters.

N and K are integers.

Input

Input is given from Standard Input in the following format:

N
S
K

Output

Print the string obtained by replacing every character in S that differs from the K-th character of S, with *.

Sample Input 1

5
error
2

Sample Output 1

*rr*r

The second character of S is r. When we replace every character in error that differs from r with *, we get the string *rr*r.

Sample Input 2

6
eleven
5

Sample Output 2

e*e*e*

Sample Input 3

9
education
7

Sample Output 3

******i**

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;

namespace B
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());
            string s = Console.ReadLine();
            int k = int.Parse(Console.ReadLine());

            char targetChar = s[k - 1];

            for(int i = 0; i < n; ++i)
            {
                if(s[i] == targetChar)
                {
                    Console.Write(targetChar);
                }
                else
                {
                    Console.Write('*');
                }
            }
            Console.WriteLine();

            Console.ReadKey();
        }
    }
}