"use strict"
function main(arg) {
    let [K, S] = arg.trim().split("\n").slice(0, 2)
    K = Number(K)
    if (S.length > K) {
        console.log(S.slice(0,K) + '...')
    } else {
        console.log(S)
    }
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));