'use strict';
const p = s => console.log(s);
// let a,b,c,d;
// [a,b,c,d] = input[0].trim().split(" ").map(i => parseInt(i));

function main(input) {
  let K = parseInt(input[0].trim().split(" ")[0]);
  let S = input[1].trim().split("");
  let result;

  if(K >= S.length) {
    result = S.join("");
  } else {
    result = S.slice(0,K).join("") + '...';
  }
  p(result);

}
main(require('fs').readFileSync('/dev/stdin', 'utf8').trim().split("\n"));
