A super simple intro to java cashier's calculator that i did for a blog post assignment thingy

CashierCalculator.java

//-----------------------------------------
// Cashier Calculator
// Written by Gersande La Fleche
//-----------------------------------------
/*
*/
import java.util.Scanner;
import java.text.DecimalFormat; // Just in case I decide to use it
import java.util.Arrays;

public class CashierCalculator {
// Initialize the calculator
	public static void main(String[] args) {

		// Initialize a new Scanner object
		Scanner scan = new Scanner(System.in);

		// Going to define the minimums and maximums that don't change in this bit
		int minnumofitems = 1;
		int maxnumofitems = 10;
		double mingrate = 0;
		double maxgrate = 18;
		double minqrate = 0;
		double maxqrate = 22;
		double minprice = 1;
		double maxprice = 1000;

		// These are user defined
		int numofitems = 0;
		double[] pricearray;

		// these are function defined
		double subtotal;
		double gst = -1;
		double qst = -1;
		double totalprice;

		// strings asking the user for stuff 
		String enteritems = "Please enter the number of items bought [1...10] : ";
		String enterprice = "Please enter the price of item ";
		String enterprice1 = " [1...1000] : ";
		String entergst = "Please enter the tax rate of GST in %% [0...100] : ";
		String enterqst = "Please enter the tax rate of QST in %% [0...100] : ";
		// now let's deal with input
		int error1 = -1;
		do {
			System.out.print(enteritems);
			numofitems = scan.nextInt();
			error1 ++;
		} while (numofitems > 10 || numofitems < 1 || numofitems == 0);
		
		// let's build the array of prices
		int error2 = 0;
		pricearray = new double[numofitems];
		int count = 0;
		int n = 1;
		do {
			do {
				System.out.print(enterprice + n + enterprice1);
				pricearray[count] = scan.nextDouble();
				if (pricearray[count] < minprice || pricearray[count] > maxprice ) { 
					error2 ++;
				}
			} while (pricearray[count] < minprice || pricearray[count] > maxprice || pricearray[count] == 0);
			count ++;	
			n ++;
		} while (count != numofitems);

		// let's figure out what is the QST RATE

		int error3 = -1;
		do {
			System.out.print(entergst);
			gst = scan.nextDouble();
			error3 ++;
		} while (gst == -1 || gst < mingrate || gst > maxgrate);

		int error4 = -1;
		do {
			System.out.print(enterqst);
			qst = scan.nextDouble();
			error4 ++;
		} while (qst == -1 || qst < minqrate || qst > maxqrate);

		// TIME TO ADD THINGS OMG

		int totalerrors = error1 + error2 + error3 + error4;
		if (totalerrors > 0) {
			System.out.println("You entered " + totalerrors + " wrong inputs.");
		}
		// A function to display the output

		subtotal = getSubtotal(pricearray, numofitems);
		System.out.println("Sub total :     $" + subtotal);

		double gst1 = getPercent(gst);
		double gstcalc = calcGST(gst1, subtotal);
		System.out.println("GST is :     $" + gstcalc);

		double qrt1 = getPercent(qst);
		double qstcalc = calcQST(qst, subtotal, gstcalc);
		System.out.println("QST is :     $" + qstcalc);

		totalprice = getTotal(subtotal,gstcalc,qstcalc);
		System.out.println("Total is :     $" + totalprice);
	}
// A function to calculate the subtotal
	public static double getSubtotal(double[] n, int a) {
		int c = 0;
		double value = 0;
		while (c != a) {
			value = value + n[c];
			c ++;
		}
		return value;
	}
// A function to calculate the GST
	public static double getPercent(double n) {
		double a = n / 100;
		return a;
	}
	public static double calcGST(double n, double a) {
		double z = a * n;
		return z;
	}
// A function to calculate the QST
	public static double calcQST(double a, double b, double c) {
		double z = (b + c) * a;
		return z;
	}
// A function to calculate the total
	public static double getTotal(double a, double b, double c) {
		double z = a + b + c;
		return z;
	}
}