#include <bits/stdc++.h>

using namespace std;

void ghiTapTin(float a[], int n) {
	ofstream ofs("DATHUC.txt");
	ofs<<n<<"\n";
	for (int i = 0; i < n; i++) {
		ofs<<a[i]<<" ";
	}
	ofs<<"\n";
	for (int i = 0; i < n; i++) {
		ofs<<a[i]<<" x "<<i;
		if (i != n-1) ofs<<" + ";
	}
	ofs.close();
}

void docTapTin() {
	string data;
	cout<<"Noi dung cua tap tin DATHUC.txt"<<endl;
	ifstream ifs("DATHUC.txt");
	while (getline(ifs, data)) {
		cout<<data<<"\n";
	}
	ifs.close();
}

int main() {
	int n;
	float a[100];
	cout<<"Nhap n: "; cin>>n;
	for (int i = 0; i < n; i++) {
		cout<<"Nhap a["<<i<<"]: ";
		cin>>a[i];
	}
	ghiTapTin(a, n);
	docTapTin();
	return 0;
}