#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)x.size()
#define D(x) cerr << #x << " = " << (x) << '\n'
using ll = long long;

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	int k;
	string s;
	cin >> k >> s;
	for(int i = 0; i < min(k, sz(s)); ++ i) cout << s[i];
	if(sz(s) > k) cout << "...";
	cout << '\n';
}
