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 (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>

int main() {
  int i, number, k;
  char special_char;
  scanf("%d", &number);
  char str[number + 1];
  scanf("%s", str);
  scanf("%d", &k);
  special_char = str[k - 1];
  for(i = 0; i < number; i++) {
    if(str[i] == special_char) {
      printf("%c", str[i]);
    } else {
      printf("*");
    }
  }
  printf("\n");
  return 0;
}