#include<iostream>
#include<string>
using namespace std;
int main(){
	int k;
	string s;
	cin>>k>>s;
	if(s.length()<=k) cout<<s<<endl;
	else{
		for(int i=0;i<k;i++){
			cout<<s[i];
		}
		cout<<"...";
	}
	return 0;
} 