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回顾:HashMap 操作

本课属于 Coddy C# 学习旅程的“逻辑与流程”单元。第 55 课,共 66 课。

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挑战

中等

创建一个名为 ProcessDictionary 的方法,对 Dictionary<string, int> 库存执行高级操作。该方法应当:

  1. 处理操作列表中的命令:
    • COUNT:打印 Total items: {count}(其中 {count} 是不同键的数量),然后打印成功消息
    • ADD item quantity:添加具有指定数量的新物品(如果物品已存在,则增加其数量),然后打印成功消息
    • REMOVE item:从库存中移除指定物品,然后打印成功或失败消息
    • UPDATE item quantity:将物品的数量设为指定值,然后打印成功或失败消息
    • FIND item:如果找到,则打印 {item}: {quantity},然后打印成功消息;如果未找到,则打印 Not found,然后打印失败消息
  2. 对于每个操作,按以下确切格式打印状态消息:
    • Operation {command} performed successfully
    • Operation {command} failed: {reason}。其中,当物品不在库存中时,{reason} 为 Item not found
  3. 返回更新后的库存字典

例如,在包含 orange: 3 的库存中处理 FIND orange,应打印:
orange: 3
Operation FIND performed successfully

当 shoes 不在库存中时处理 REMOVE shoes,应打印:
Operation REMOVE failed: Item not found

亲手试试

using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;

class Program
{
    public static Dictionary<string, int> ProcessDictionary(Dictionary<string, int> inventory, List<string> operations)
    {
        // 在这里编写你的代码
        
        return inventory;
    }
    
    static void Main(string[] args)
    {
        Dictionary<string, int> inventory = new Dictionary<string, int>();
        List<string> operations = new List<string>();
        
        // 读取第一行,检查库存是否采用 JSON 格式
        string firstLine = Console.ReadLine();
        
        // 检查库存输入是否为 JSON 格式
        if (firstLine != null && firstLine.StartsWith("{") && firstLine.EndsWith("}"))
        {
            try
            {
                // 处理库存的 JSON 输入
                string jsonContent = firstLine.Substring(1, firstLine.Length - 2);
                
                // 按引号外的逗号拆分
                string pattern = @",(?=(?:[^""]*""[^""]*"")*[^""]*$)";
                string[] entries = Regex.Split(jsonContent, pattern);
                
                foreach (string entry in entries)
                {
                    // 使用正则表达式提取键和值
                    Match match = Regex.Match(entry, @"""([^""]+)""\s*:\s*(\d+)");
                    if (match.Success)
                    {
                        string keyMatch = match.Groups[1].Value;
                        int valueMatch = int.Parse(match.Groups[2].Value);
                        inventory.Add(keyMatch, valueMatch);
                    }
                }
                
                // Read second line for operations
                string secondLine = Console.ReadLine();
                
                // Check if operations are in JSON array format
                if (secondLine != null && secondLine.StartsWith("[") && secondLine.EndsWith("]"))
                {
                    try
                    {
                        // Extract content between square brackets
                        string arrayContent = secondLine.Substring(1, secondLine.Length - 2);
                        
                        // Use regex to match all quoted strings - this is more robust
                        MatchCollection matches = Regex.Matches(arrayContent, @"""([^""]*)""");
                        
                        foreach (Match match in matches)
                        {
                            // Add the captured group (without quotes)
                            if (match.Groups.Count > 1)
                            {
                                operations.Add(match.Groups[1].Value);
                            }
                        }
                    }
                    catch (Exception ex)
                    {
                        Console.WriteLine($"Error parsing operations array: {ex.Message}");
                        return;
                    }
                }
                else
                {
                    // Process operations in traditional format
                    int m = int.Parse(secondLine);
                    for (int i = 0; i < m; i++)
                    {
                        operations.Add(Console.ReadLine());
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Error parsing JSON input: {ex.Message}");
                return;
            }
        }
        else
        {
            // Process traditional input format
            int n = int.Parse(firstLine);
            for (int i = 0; i < n; i++)
            {
                string[] parts = Console.ReadLine().Split(':');
                inventory.Add(parts[0], int.Parse(parts[1]));
            }
            
            // Read operations
            int m = int.Parse(Console.ReadLine());
            for (int i = 0; i < m; i++)
            {
                operations.Add(Console.ReadLine());
            }
        }
        
        Dictionary<string, int> result = ProcessDictionary(inventory, operations);
        
        // Print updated inventory
        Console.WriteLine("Final Inventory:");
        foreach (var item in result)
        {
            Console.WriteLine($"{item.Key}: {item.Value}");
        }
    }
}

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