import std.stdio, std.array, std.conv, std.string, std.range, std.algorithm;


void main() {
    long n = readln.strip.to!(long);
    string s = readln.strip;
    long k = readln.strip.to!(long);

    writeln(cast(dchar[])(s.map!(c => (c == s[k-1]) ? c : '*').array));
}
