Question

在这里我需要任何帮助。我在CS50课程中解决了问题5，并且代码成功编译，当我手动测试它时，它没有问题。但是我尝试用$ check50 cs50/problems/2020/x/speller进行检查，并给了this result。

// Implements a dictionary's functionality

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <ctype.h>
#include "dictionary.h"

// Represents a node in a hash table
typedef struct node
{
    char word[LENGTH + 1];
    struct node *next;
}
node;

char oneword[LENGTH + 1];
int counter = 0 ;

// Number of buckets in hash table
const int HASHTABLE_SIZE = 65536;
// Hash table
node *table[HASHTABLE_SIZE];

// Returns true if word is in dictionary else false
bool check(const char *word)
{
    // TODO
    char lowerWord[LENGTH + 1];

    for (int i = 0; i <LENGTH; i++)
    {
        lowerWord[i] = tolower(word[i]);
    }

    int x = hash (lowerWord);


    for (node *tmp =  table[x] ; tmp != NULL; tmp = tmp->next)
    {
        if (strcasecmp(tmp->word, word)==0)
        {
             return true;
        }
    }
    return false;
}

// Hashes word to a number
//https://www.reddit.com/r/cs50/comments/1x6vc8/pset6_trie_vs_hashtable/cf9nlkn/
unsigned int hash(const char *word)
{
    unsigned int hash = 0;
    for (int i=0, n=strlen(word); i<n; i++)
    hash = (hash << 2) ^ word[i];
    return hash % HASHTABLE_SIZE;
}


// Loads dictionary into memory, returning true if successful else false
bool load(const char *dictionary)
{
    // TODO
    FILE *dict = NULL;
    dict = fopen("dictionaries/large", "r");
    int x = 0;

    table[x] = malloc(sizeof(node));
    if (dict != NULL)
    {

        while (true)
        {
             if (feof(dict))
            {
                 break;
            }


            fscanf (dict, "%s", oneword);
            node *h = malloc(sizeof(node));
            if (h == NULL)
            {
                return 1;
            }

            strcpy(h->word, oneword);

            h->next = NULL;

            x = hash (h->word);

            h->next = table[x];
            table[x] = h;

            counter++;


        }
    }
    fclose(dict);
    return true;
}

// Returns number of words in dictionary if loaded else 0 if not yet loaded
unsigned int size(void)
{
    return counter;
}

// Unloads dictionary from memory, returning true if successful else false
bool unload(void)
{
    // TODO
    node *cursor= NULL;
    for (int i = 0; i > HASHTABLE_SIZE; i++)
    {
        for (cursor =  table[i] ; cursor != NULL; cursor = cursor->next)
        {
            node *tmp = cursor;
            cursor = cursor->next;
            free (tmp);

        }
       free (cursor); 
    }
    return true;
}

Answer 1

仔细查看check50报告中的“单词词典”结果。它没有使用大型词典。该程序被硬编码查找“字典/大”，并且它不会检测到fopen是否成功。可以推测CS50服务器上不存在“字典/大字典”，并且该程序立即由于分段错误而失败。

CS50 pset5 Speller我的代码可以正常运行，但check50不能正常运行

1 个答案: