function Main(input) {
	var str = input;
	str = str.split("\n");
	const MAX_LENGTH = Number(str[0].split(" ")); 
	const STRING = str[1]; 
	var  mod = "";
	if(STRING.length > MAX_LENGTH){
  		mod = STRING.substr(0, MAX_LENGTH) + '...'
	}else{
		mod = STRING;
	}
	
console.log(mod); 
}
 //*おまじない
Main(require("fs").readFileSync("/dev/stdin", "utf8"));
