#include <iostream>
#include <cstdlib>
using namespace std;
int n;
struct date{
	int day, month, year;
};
class datefile{
	date *d;
	public:
		datefile()
		{
			d=(date*)malloc(n*sizeof(date));
			for(int i=0;i<n;i++)
			{
				d[i].day=0;
				d[i].month=0;
				d[i].year=0;
			}
		}
		void writedate()
		{
			for(int i=0;i<n;i++)
			{
				printf("enter day month year:\n");
				scanf("%2d %2d %4d",&d[i].day,&d[i].month,&d[i].year);
			}
		}
		void safefile()
		{
			FILE *f=fopen("f.txt","w");
			for(int i=0;i<n;i++)
			{
				fprintf(f,"%2d %2d %4d",d[i].day,d[i].month,d[i].year);
			}
			fclose(f);
		}
	int minyear(void)
	{
		int min_year=d[0].year;
		for(int i=0;i<n;i++)
		{
			if(d[i].year>d[i++].year)
			min_year=d[i++].year;
		}
		return min_year;
	}
	void showlastdate()
	{
		int lastyear=d[0].year;
		int lastmonth=d[0].month;
		int lastday=d[0].year;
		printf("last date:\n");
		for(int i=0;i<n;i++)
		{
			if(d[i].day<d[i++].day)
			lastday=d[i++].day;
			if(d[i].month<d[i++].month)
			lastmonth=d[i+1].month;
			if(d[i].year<d[i++].year)
			lastyear=d[i++].year;
		}
		printf("%d.%d.%4d\n",lastday,lastmonth,lastyear);
	}
	void spring()
	{
		printf("spring dates:\n");
		for(int i=0;i<n;i++)
		{
			if(d[i].month<6 && d[i].month>2)
			printf("%2d %2d %4d\n",d[i].day,d[i].month,d[i].year);
		}
	}
};
int main()
{
	printf("enter an ammount of dates:\n");
	scanf("%d",&n);
	datefile d1;
	d1.writedate();
	d1.safefile();
	cout<<"least year"<<d1.minyear()<<endl;
	d1.showlastdate();
	d1.spring();
	return 0;
}