Pennies For Days

Pennies.java

/*
 * Name: Geoffrey Zoref
 * Date: 10/10/2018
 * Project: Classes and Objects - Ch. 6
 */

import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.util.Scanner;

public class Pennies {


    public static void main(String[] args) {
        // Declare var to store number of days worked
        int numDays;

        // User salary
        double salary = 0.01;
        double totalSalary = 0.01;

        // Create scanner object
        NumberFormat df;
        try (Scanner keyboard = new Scanner(System.in)) {


            // Decimal formating for salary variables
            df = DecimalFormat.getInstance();
            df.setMaximumFractionDigits(2);

            // Prompt user for input
            System.out.print("Enter the number of days worked: ");
            numDays = keyboard.nextInt();

            // Input validation: Input must not be less than 1
            while (numDays < 1) {
                System.out.print("Enter the number of days worked: ");
                numDays = keyboard.nextInt();
            }
        }

        // Display table header
        System.out.println("Day  " + "   Salary     " + "Total Salary");

        // Display number of days
        int day = 1;

        // Construct while loop to display days, daily salary, and total salary.
        while (numDays > 0) {
            System.out.println(day + "       $" + salary + "       $" + df.format(totalSalary));
            salary *= 2;
            totalSalary += salary;
            day++;
            numDays--;
        }
    }
}


/**
 * Write  a  program  that  calculates  how  much  a  person  would  earn  over  a  period  of  time  if his or her
 * salary is one penny the first day, two pennies the second day, and continues to double each day. The program should
 * display a table showing the salary for each day, and then show the total pay at the end of the period. The output
 * should be displayed in a dollar amount, not the number of pennies.
 * <p>
 * Input Validation: Do not accept a number less than one for the number of days worked
 * <p>
 * n(n+1)/2
 */