How to move decimals and show specific number? C++ - c++

Question

Hello I'm here as a last resort. For this assignment, I have been unable to figure out certain things like how to show a decimal as a whole number. For example, .29 should be 29.00. I also don't know how to show the number of items properly as in if there's 2 items(3 eggs and 2 cheeses),how do I only show 2 items instead of 5?
I have attached the guidelines for this assignment and what I have so far. Thank you for your help!
Part A
Your program should obtain the following information from the user upon startup:
• Name of the cashier.
• State that store is located in (Arizona, New York, etc)
• Date (separated into day, month and year)
Part B
The program should display a welcome message to the user in the following format:
Hello (cashier name) Welcome to Cashier App.
You are currently cashing for a store located in (state).
Today’s date is (date).
The program should allow the user to enter, for an unlimited number of products, the name of the product, the price and the quantity being purchased. The program must calculate the amount of tax to add to the price, depending on which of the following three states the program is being used in:

New York - 9.75%
New Jersey - 8.25%
Connecticut - 7.5%
Tennessee - 4.5%
All Others - 10%
After calculating the total amount owed for a single product, the program should display the name of the product and the total and then ask the user whether or not they would like to enter another product i.e.
Eggs - $10.74 

Would you like to enter another product?
After the user has entered all of their products, you should display a summary of the purchases that tells the user how many items were entered and the total amount due i.e.
You have entered 14 products. Your total amount owed is $845.89
#include <iostream>
using namespace std;
int main() {
string state, month, day, year, cashierName, productName;
char YorN;
float price, tax, productTotal, productQuantity, totalQuantity = 0, total = 0;
cout << "Enter name: ";
cin >> cashierName;
cout << "Are you in NY, NJ, CT, TN, or other?: ";
cin >> state;
cout << "Enter month: ";
cin >> month;
cout << "Enter day: ";
cin >> day;
cout << "Enter year: ";
cin >> year;
cout << "Hello " << cashierName << ". Welcome to Cashier App.\n";
cout << "You are currently cashing for a store located in " << state << ".\n";
cout << "Today's date is " << month << " " << day << ", " << year << ".\n";
if(state == "NY" || state == "ny") {
tax = .0975;
}
else if (state == "NJ" || state == "nj") {
tax = .0825;
}
else if (state == "CT" || state == "ct") {
tax = .075;
}
else if (state == "TN" || state == "tn") {
tax = .045;
}
else {
tax = .1;
}
cout << "Do you want to add a product to your cart? (Y/N) ";
cin >> YorN;
while(YorN == 'Y' || YorN == 'y') {
cout << "Enter product name: ";
cin >> productName;
cout << "Enter price: ";
cin >> price;
cout << "Enter quantity: ";
cin >> productQuantity;
productTotal = price * productQuantity * tax;
total = productTotal + total;
totalQuantity = productQuantity + totalQuantity;
int nProductTotal = int(productTotal * 100);
productTotal = ((float)nProductTotal)/100;
int nTotal = int(total * 100);
total = ((float)nTotal)/100;
cout << productName << " - $" << productTotal << endl;
cout << "Would you like to enter another another product? (Y/N) ";
cin >> YorN;
}
cout << "You have entered " << totalQuantity << " products. Your total amount owed is $" << total << ".\n";
return 0;
}

Answer 1

To show the number of different products you can count them with
...
int totalQuantity(0);
while(YorN == 'Y' || YorN == 'y') {
++totalQuantity;
...
// remove totalQuantity = productQuantity + totalQuantity;
...
}
cout << "You have entered " << totalQuantity << " products. Your total amount owed is $" << total << ".\n";
...
totalQuantity should be of type int and not float as you can't buy 2.2 different products. To round the values to two decimals you can use
productTotal = std::round(price * productQuantity * tax * 100)/100;
Please avoid c style casts like
(float)nTotal
The c++ way to do this is
static_cast<float>(nTotal);
I don't understand what you mean with .29 should be 29.00 but you can achieve this with
double a = 100 * .29;
or
int a = std::round(100 * .29);
or
cout << std::setprecision(2) << 0.29 * 100 << '\n';