更新库存数量

package main

import (
	"errors"
	"fmt"
	"sort"
	"strconv"
	"strings"
)

type Product struct {
	Price    float64
	Quantity int
}

func addNewItem(inventory map[string]Product, productName string, price float64, quantity int) error {
	if _, exists := inventory[productName]; exists {
		return errors.New("product already exists: " + productName)
	}
	inventory[productName] = Product{Price: price, Quantity: quantity}
	return nil
}

func main() {
	var existingInventory string
	var newProducts string
	fmt.Scanln(&existingInventory)
	fmt.Scanln(&newProducts)

	inventory := make(map[string]Product)

	// Parse existing inventory
	existingItems := strings.Split(existingInventory, ",")
	for _, item := range existingItems {
		parts := strings.Split(item, ":")
		name := parts[0]
		price, _ := strconv.ParseFloat(parts[1], 64)
		quantity, _ := strconv.Atoi(parts[2])
		inventory[name] = Product{Price: price, Quantity: quantity}
	}

	// Parse new products to add
	newItems := strings.Split(newProducts, ",")
	
	fmt.Println("Adding New Items:")
	
	itemsProcessed := 0
	itemsAdded := 0
	itemsRejected := 0
	var rejectedProducts []string

	for _, item := range newItems {
		parts := strings.Split(item, ":")
		name := parts[0]
		price, _ := strconv.ParseFloat(parts[1], 64)
		quantity, _ := strconv.Atoi(parts[2])
		
		itemsProcessed++
		
		err := addNewItem(inventory, name, price, quantity)
		if err != nil {
			fmt.Printf("%s: Failed to add - %s\n", name, err.Error())
			itemsRejected++
			rejectedProducts = append(rejectedProducts, name)
		} else {
			fmt.Printf("%s: Successfully added - $%.2f (Stock: %d)\n", name, price, quantity)
			itemsAdded++
		}
	}

	// Addition summary
	fmt.Println("Addition Summary:")
	fmt.Printf("Items processed: %d\n", itemsProcessed)
	fmt.Printf("Items added: %d\n", itemsAdded)
	fmt.Printf("Items rejected: %d\n", itemsRejected)

	// Display updated inventory in alphabetical order
	fmt.Println("Updated Inventory:")
	var productNames []string
	for name := range inventory {
		productNames = append(productNames, name)
	}
	sort.Strings(productNames)

	totalProducts := 0
	totalItems := 0
	totalValue := 0.0

	for _, name := range productNames {
		product := inventory[name]
		fmt.Printf("- %s: $%.2f (Stock: %d)\n", name, product.Price, product.Quantity)
		totalProducts++
		totalItems += product.Quantity
		totalValue += product.Price * float64(product.Quantity)
	}

	// Final inventory statistics
	fmt.Println("Final Inventory Statistics:")
	fmt.Printf("Total Products: %d\n", totalProducts)
	fmt.Printf("Total Items in Stock: %d\n", totalItems)
	fmt.Printf("Total Inventory Value: $%.2f\n", totalValue)

	// List rejected products
	if len(rejectedProducts) > 0 {
		fmt.Printf("Rejected products: %s\n", strings.Join(rejectedProducts, ","))
	} else {
		fmt.Println("All new products were added successfully")
	}
}