c++入出力ストリーム演算子のリロードテストコード

#pragma once
#include
using namespace std;
class Data
{
private:
	int year;
	int month;
	int day;
public:
	Data(int year=0,int month=0,int day=0) :year(year),month(month),day(day){}
	friend istream& operator>>(istream&,Data&);
	friend ostream& operator<

 

#include "Data.h"
istream& operator>>(istream& in, Data& a) 
{
	in >> a.year >> a.month >> a.day;
	return in;
}
ostream& operator<

#include "Data.h"
int main()
{
	Data t[3];
	for (int i = 0; i < 3; i++)
		cin >> t[i];
	for (int i = 0; i < 3; i++)
		cout<< t[i];
	return 0;
}