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 Rust (1.15.1) (judge verdict: Accepted)

fn read<T: ::std::str::FromStr>() -> T {
    let mut s = String::new();
    ::std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: ::std::str::FromStr>() -> Vec<T> {
    let mut s = String::new();
    ::std::io::stdin().read_line(&mut s).ok();
    s.trim().split_whitespace()
        .map(|e| e.parse().ok().unwrap()).collect()
}

pub fn main() {
    let N: usize = read();
    let S: String = read();
    let K: usize = read();
    let target_char = S.chars().nth(K - 1).unwrap();
    let mut ans = String::with_capacity(N);
    for c in S.chars() {
        ans.push(if c == target_char { c } else { '*' });
    }
    println!("{}", ans);
}