function main(input) {
	let input = input.split("\n");
  	let k = pathInt(input[0], 10);
  	let s = input[1];
  
  	console.log(
      s.slice(0, k) + 
      ((k === s.length)? "" : "...")
    );
}
 
main(require('fs').readFileSync('/dev/stdin', 'utf8'));