#include <stdio.h>
#include <string.h>

int main()
{
	int		k,slen;
	char	s[101];
	char	ans[103];

	s[0] = '\0';
	scanf("%d", &k);
	scanf("%s", s);

	slen = strlen(s);

	if(k >= slen)
	{
		strcpy(ans, s);
	}
	else
	{
		strncpy(ans, s, k);
		ans[k+0] = '.';
		ans[k+1] = '.';
		ans[k+2] = '.';
		ans[k+3] = '\0';
	}

	printf("%s\n", ans);

    return 0;
}
