C#期中卡牌操作程序仅获80分，无测试用例求错误排查

我帮朋友完成C#期中试题，其他题目都已解决，但最后一道卡牌操作题仅拿到80分，系统仅显示"Incorrect Answer"错误，没有类似LeetCode的测试用例可供调试。题目及示例输入输出可通过图片查看。

Python版本代码 #

deck = input().split(', ')
n = int(input())


def add(deck,command):
    cardname = command[1]
    if cardname in deck:
        return 'Card is already in the deck'
    deck.append(cardname)
    return 'Card successfully added'


def remove(deck,command):
    cardname = command[1]
    if cardname in deck:
        deck.remove(cardname)
        return 'Card successfully removed'
    return 'Card not found'


def removeat(deck,command):
    index = int(command[1])
    if index not in range(len(deck)):
        return 'Index out of range'
    deck.pop(index)
    return 'Card successfully removed'


def insert(deck,command):
    index = int(command[1])
    cardname = command[2]
    if index not in range(len(deck)):
        return 'Index out of range'
    if cardname in deck and index in range(len(deck)):
        return 'Card is already in the deck'
    deck.insert(index,cardname)
    return 'Card successfully added'


for i in range(n):
    command = input().split(', ')
    if command[0]== 'Add' and len(command) ==2:
        print(add(deck,command))
    elif command[0]== 'Remove' and len(command) ==2:
        print(remove(deck,command))
    elif command[0]== 'Remove At'and len(command) ==2:
        print(removeat(deck,command))
    elif command[0]== 'Insert'and len(command) ==3:
        print(insert(deck,command))

print(', '.join(deck))

转换后的C#版本代码 #

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        List<string> deck = new List<string>(Console.ReadLine().Split(", "));
        int n = int.Parse(Console.ReadLine());

        for (int i = 0; i < n; i++)
        {
            string[] command = Console.ReadLine().Split(", ");
            if (command.Length == 2 && command[0] == "Add")
            {
                Console.WriteLine(Add(deck, command));
            }
            else if (command.Length == 2 && command[0] == "Remove")
            {
                Console.WriteLine(Remove(deck, command));
            }
            else if (command.Length == 2 && command[0] == "Remove At")
            {
                Console.WriteLine(RemoveAt(deck, command));
            }
            else if (command.Length == 3 && command[0] == "Insert")
            {
                Console.WriteLine(Insert(deck, command));
            }
        }

        Console.WriteLine(string.Join(", ", deck));
    }

    static string Add(List<string> deck, string[] command)
    {
        string cardName = command[1];

        if (deck.Contains(cardName))
        {
            return "Card is already in the deck";
        }

        deck.Add(cardName);
        return "Card successfully added";
    }

    static string Remove(List<string> deck, string[] command)
    {
        string cardName = command[1];

        if (deck.Contains(cardName))
        {
            deck.Remove(cardName);
            return "Card successfully removed";
        }

        return "Card not found";
    }

    static string RemoveAt(List<string> deck, string[] command)
    {
        int index = int.Parse(command[1]);

        if (index >= 0 && index < deck.Count)
        {
            deck.RemoveAt(index);
            return "Card successfully removed";
        }

        return "Index out of range";
    }

    static string Insert(List<string> deck, string[] command)
    {
        int index = int.Parse(command[1]);
        string cardName = command[2];

        if (index >= 0 && index <= deck.Count)
        {
            if (deck.Contains(cardName) && index >= 0 && index < deck.Count)
            {
                return "Card is already in the deck";
            }

            deck.Insert(index, cardName);
            return "Card successfully added";
        }

        return "Index out of range";
    }
}

可能的错误点及修正建议 #

1. Insert操作的索引逻辑不一致
   Python版本中，Insert要求索引必须满足0 <= index < len(deck)，而C#版本允许index == deck.Count（即插入到列表末尾），这会导致两种代码逻辑差异。若题目要求Insert不能插入到末尾，C#代码就会出错。

2. Insert操作的卡片存在性判断冗余
   C#的Insert方法中，判断卡片存在的条件额外加了index >=0 && index < deck.Count，导致当index == deck.Count时，即使卡片已存在也会执行插入，违反题目要求。

修正后的C# Insert方法

static string Insert(List<string> deck, string[] command)
{
    int index = int.Parse(command[1]);
    string cardName = command[2];

    // 和Python逻辑对齐，索引范围限制为0到deck.Count-1
    if (index >= 0 && index < deck.Count)
    {
        if (deck.Contains(cardName))
        {
            return "Card is already in the deck";
        }

        deck.Insert(index, cardName);
        return "Card successfully added";
    }

    return "Index out of range";
}

内容的提问来源于stack exchange，提问作者Peter