function Main(input) {
    tmp = input.split("\n");
    k = parseInt(tmp[0], 10);
    s = tmp[1];
    long = s.length;

    if (k >= long) {
        console.log(s);        
    } else{
        cut = s.substr(0, k);
        console.log( + '...');
    }    
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));