
function Main(input) {
    input = input.trim();
    input = input.split("\n")
    var a = parseInt(input[0])
    if(input[1].length<=a){console.log(input[1])}else{
        console.log(input[1].slice(0,a)+"...")
    }



}

Main(require("fs").readFileSync("/dev/stdin", "utf8")); 
