Example: Interactive Bill Generator in C++

// Interactive Bill Generator
#include <iostream>
#include <vector>   // For std::vector
#include <string>   // For std::string
#include <iomanip>  // For formatting

struct BillItem {
    std::string name;
    int quantity;
    double price;
    double total;
};

int main() {
    // Step 1: Initialize variables
    std::vector<BillItem> items;
    double subtotal = 0.0;
    char addMore = 'y';
    int itemCounter = 1;

    // Step 2: Loop to get item details from user
    while (addMore == 'y' || addMore == 'Y') {
        BillItem currentItem;
        std::cout << "\nEnter details for Item " << itemCounter << ":\n";
        std::cout << "Enter item name: ";
        std::cin.ignore(); // Consume the newline character left by previous cin
        std::getline(std::cin, currentItem.name);

        std::cout << "Enter quantity: ";
        std::cin >> currentItem.quantity;

        std::cout << "Enter price per item: $";
        std::cin >> currentItem.price;

        currentItem.total = currentItem.quantity * currentItem.price;
        items.push_back(currentItem);
        subtotal += currentItem.total;

        std::cout << "Add another item? (y/n): ";
        std::cin >> addMore;
        itemCounter++;
    }

    // Step 3: Calculate Tax and Grand Total
    double taxRate = 0.08; // 8% tax
    double taxAmount = subtotal * taxRate;
    double grandTotal = subtotal + taxAmount;

    // Step 4: Print the bill
    std::cout << "\n----------------------------------------\n";
    std::cout << std::setw(20) << "YOUR RECEIPT\n";
    std::cout << "----------------------------------------\n";
    std::cout << std::left << std::setw(15) << "Item"
              << std::right << std::setw(5) << "Qty"
              << std::right << std::setw(10) << "Price"
              << std::right << std::setw(10) << "Total\n";
    std::cout << "----------------------------------------\n";

    // Step 5: Print individual item details from vector
    for (const auto& item : items) {
        std::cout << std::left << std::setw(15) << item.name
                  << std::right << std::setw(5) << item.quantity
                  << std::right << std::setw(10) << std::fixed << std::setprecision(2) << item.price
                  << std::right << std::setw(10) << std::fixed << std::setprecision(2) << item.total << "\n";
    }
    std::cout << "----------------------------------------\n";

    // Step 6: Print summary totals
    std::cout << std::left << std::setw(25) << "Subtotal:"
              << std::right << std::setw(15) << std::fixed << std::setprecision(2) << subtotal << "\n";

    std::cout << std::left << std::setw(25) << "Tax (" << (taxRate * 100) << "%):"
              << std::right << std::setw(15) << std::fixed << std::setprecision(2) << taxAmount << "\n";

    std::cout << "----------------------------------------\n";

    std::cout << std::left << std::setw(25) << "Grand Total:"
              << std::right << std::setw(15) << std::fixed << std::setprecision(2) << grandTotal << "\n";
    std::cout << "----------------------------------------\n";
    std::cout << "Thank You!\n";

    return 0;
}