Everything is correct in my Check50 but in program I have other ERRORS - PSET05 Speller

Question

I hope you're doing well and I also hope you might help me. When I run my CHECK50 in my speller program. Everything is correct all green, but when I run my program or valgrind I have some errors. And I don't know why it's happening. Can you help me on these ones, please? It'd appreciated.

My check50:

https://submit.cs50.io/check50/c852723fefd803291052edf373b0a1320d11c068

My Output:

a                                                             <
Sebastian's                                                     Sebastian's
combo's                                                         combo's
Mia                                                             Mia
Sebastian's                                                     Sebastian's
Mia                                                             Mia
Mia                                                             Mia
Mia                                                             Mia
a                                                             <
MIA                                                             MIA
Mia                                                             Mia
A                                                             <
a                                                             <
Mia                                                             Mia
a                                                             <
Mia                                                             Mia
Sebastian's                                                     Sebastian's
L                                                               L
A                                                             <

WORDS MISSPELLED:     1470                                    | WORDS MISSPELLED:     955
WORDS IN DICTIONARY:  143091                                    WORDS IN DICTIONARY:  143091
WORDS IN TEXT:        17756                                     WORDS IN TEXT:        17756
TIME IN load:         0.02                                    | TIME IN load:         0.04
TIME IN check:        0.03                                    | TIME IN check:        0.02
TIME IN size:         0.00                                      TIME IN size:         0.00
TIME IN unload:       0.00                                    | TIME IN unload:       0.03
TIME IN TOTAL:        0.05                                    | TIME IN TOTAL:        0.09

My valgrind:

==23694== Memcheck, a memory error detector
==23694== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
==23694== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==23694== Command: ./speller texts/pneumonoultramicroscopicsilicovolcanoconiosis.txt
==23694== 
==23694== Conditional jump or move depends on uninitialised value(s)
==23694==    at 0x109A13: hash (dictionary.c:78)
==23694==    by 0x109B53: load (dictionary.c:131)
==23694==    by 0x1092CB: main (speller.c:40)
==23694==  Uninitialised value was created by a heap allocation
==23694==    at 0x4848899: malloc (in /usr/libexec/valgrind/vgpreload_memcheck-amd64-linux.so)
==23694==    by 0x109B14: load (dictionary.c:121)
==23694==    by 0x1092CB: main (speller.c:40)
==23694== 
...
==23694== 
==23694== HEAP SUMMARY:
==23694==     in use at exit: 0 bytes in 0 blocks
==23694==   total heap usage: 143,096 allocs, 143,096 frees, 8,023,256 bytes allocated
==23694== 
==23694== All heap blocks were freed -- no leaks are possible
==23694== 
==23694== For lists of detected and suppressed errors, rerun with: -s
==23694== ERROR SUMMARY: 2 errors from 1 contexts (suppressed: 0 from 0)

My code:

// Implements a dictionary's functionality

#include <math.h>
#include <ctype.h>
#include <cs50.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <strings.h>

#include "dictionary.h"

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

// TODO: Choose number of buckets in hash table
const unsigned int N = 17576;

// Hash table
node *table[N];

//Dictionary Word
char dicword[LENGTH + 1];

//Variable that keeps track of the number of words in the dictionary
int number_words = 0;

// Returns true if word is in dictionary, else false
bool check(const char *word)
{
    // TODO
    unsigned int index_valuetocheck;
    // Using the hash function in the input word
    index_valuetocheck = hash(word);
    // Access to the correct index into the hash table
    node *ptr = table[index_valuetocheck];
    //Checking if the word is in the hash table
    while (ptr != NULL)
    {
        // Comparing the input word with the word in the dictionary
        if (strcasecmp(word, ptr->word) == 0)
        {
            return true;
        }
        //Otherwise go to the next node of the linked list
        ptr = ptr->next;
    }
    return false;
}

// Hashes word to a number
unsigned int hash(const char *word)
{
    // TODO: Improve this hash function
    char word1 = word[0];
    char word2 = word[1];
    char word3 = word[2];
    int char1 = 0;
    int char2 = 0;
    int char3 = 0;
    int char1_index = 0;
    int char2_index = 0;
    int char3_index = 0;
    if (word1 != '\0')
    {
        char1 = toupper(word[0]);
    }
    if (word2 != '\0')
    {
        char2 = toupper(word[1]);
    }
    if (word3 != '\0')
    {
        char3 = toupper(word[2]);
    }

    if (char3 >= 65)
    {
        char3_index = char3 - 'A';
    }
    if (char2 >= 65)
    {
        char2_index = char2 - 'A';
    }
    int char2_char3_t = char2_index * 26 + char3_index;
    if (char1 >= 65)
    {
        char1_index = char1 - 'A';
    }
    int char1_char2_char3_t = char1_index * 676 + char2_char3_t;
    unsigned int index_value = char1_char2_char3_t;

    if (index_value > N)
    {
        index_value = index_value % N;
    }

    return index_value;
}

// Loads dictionary into memory, returning true if successful, else false
bool load(const char *dictionary)
{
    // TODO
    unsigned int newindex;
    // Open the di

Answer 1

Valgrind is catching something that check50 doesn't look for. There is an issue with your hash function. It can't deal with one-letter words like "a".

Consider that when the word is 1 letter long, word[0] is the letter, word[1] is the EOS char and word[2] is never created. When the following line is executed, word3 is not assigned anything because word[2] doesn't exist. Interestingly, it won't throw an error. (It's based in historical reasons related to c development.)

    char word3 = word[2];

It's unhappy with word3 not being initialized.

The hash function needs additional code to deal with this.

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