function main(input) {
  const [
    N, S, K
  ] = input.split("\n")
  const t = S.charAt(parseInt(K-1))
  var temp = ""
  for (var i = 0; i < S.length; i++) {
    var char = t == S[i]
      ? t
      : "*"
    temp = temp+char
  }
  console.log(temp);
}