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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <unordered_map>
#include <unordered_set>

using namespace std;

typedef unsigned long long ull;
typedef unsigned int uint;
typedef unsigned char uchar;
#define umap unordered_map
const static ull INVALID_DIGIT = ~(ull)0;

int main()
{
    int N, K;
    string S;
    cin >> N;
    cin >> S;
    cin >> K;

    char targetChar = S[K - 1];

    for (size_t i = 0; i < N; i++) {
        if (S[i] != targetChar) {
            S[i] = '*';
        }
    }
    cout << S << endl;

    return 0;
}