#include <iostream>
#include <iomanip>   //for setw
#include <cstdlib>
using namespace std;

//If p is a pointer, p[0] means the same thing as *p 

int main()
{
	double a[] {     //Gpd news: the stock price is trending upwards.
		120.00,
		130.25,
		126.00,
		121.00,
		132.50,
		128.00,
		122.00,
		133.75,
		128.95
	};
	int n {size(a)};   //how many prices in the array

	for (int i {1}; i < n-1; ++i) {
		cout << "$" << fixed << setprecision(2) 
			<< (a[i-1] + a[i] + a[i+1]) / 3 << "\n";
	}

	cout << "\n";

	for (double *p {begin(a) + 1}; p < end(a) - 1; ++p) {
		cout << "$" << fixed << setprecision(2) 
			<< (p[-1] + p[0] + p[1]) / 3 << "\n";
	}

	return EXIT_SUCCESS;
}