function Main(input){
	input = input.split("\n");
	var n = input[2];
	var arr = input[1].split("");
	var s = arr[n-1];
	for(var i=0;i<arr.length;i++){
		if(arr[i]!=s) arr[i] = "*";
	}
	console.log(arr.join(""))
}Main(require("fs").readFileSync("/dev/stdin", "utf8").trim());