import std.stdio;
import std.string;
import std.conv;
import std.array;

void main()
{
    ulong N = readln.split[0].to!ulong;
    char[] S = readln.chomp.to!(char[]);
    ulong K = readln.split[0].to!ulong;

    foreach (i; 0..N) if (S[i] != S[K - 1]) S[i] = '*';
    writeln(S.to!string);
}

