fun main(args: Array<String>) {
    val n = Integer.parseInt(readInputLine())
    val s = readInputLine()
    val k = Integer.parseInt(readInputLine())
    
    val notReplaceChar = s.get(k - 1)
    val charList = s.toCharArray().map { c -> if (c != notReplaceChar) {'*'} else {c}}
    var res = ""
    for (c in charList) {
        res = res + c.toString()
    }
    println(res)
}

fun readInputLine(): String {
    return readLine()!!
}
