#include<stdio.h>

int main(){
	int K;
	char s[110] = {};
	char res[110] = {};
	
	scanf("%d",&K);
	scanf("%s",&s);
	
	int lon = 0;
	int i = 0;
	for(i = 0;i < 110;i++){
		if(s[i])
			lon++;
	}
	
	if(lon <= K)
		printf("%s",s);
	else{
		for(i = 0;i < K;i++){
			printf("%c",s[i]);
		}
		
		printf("...");
	}
	
	
	
} 