PSET 5 Words not loading in memory

Question

I think there might be something wrong with the fscanf use because when using gbd temp's value never changes, it stays as NULL. Also, word's value stays as 0 throughout the entire program and every word in the text file appears as misspelled. Can someone help me find the error?

 bool load(const char* dictionary)
{

    root = newnode();

    //open dictionary file
    FILE* dict = fopen(dictionary, "r");
    if (dict == NULL)
    {
        printf("Could not open dictionary\n");
        return false;
    }

    //retrieve words from dictionary
    char* temp = NULL;

    while (fscanf(dict, "%s", temp) == 1)
    {
        insert(root, temp);
        words++;
    }

    return true;
}

NOTE: root and words variables are global variables.

Relevant code:

#define ALEN 27

//global variables 
node* root;
int words;

//trie nodes' definition.
typedef struct trie
{
    bool is_word;
    struct trie* children[ALEN];
} node;

    //create a node
node* newnode(void)
{
    node* new_node = malloc(sizeof(node));
    new_node->is_word = false;
    for (int i = 0; i < ALEN; i++)
    {
        new_node->children[i] = NULL;
    }
    return new_node;
}

//insert word into trie
void insert(node* root, char* temp)
{
    int len = strlen(temp);
    node* trav = root;

    for (int i = 0; i < len; i++)
    {
        if (trav->children[temp[i] - 'a'] == NULL)
        {
            trav->children[temp[i] - 'a'] = newnode();
        }

        trav = trav->children[temp[i] - 'a'];
    }
    trav->is_word = true;
}

Answer 1

I'm highly suspicious of the following two lines:

char* temp = NULL;
while (fscanf(dict, "%s", temp) == 1)

The temp var is a pointer set to NULL, which you then try to read a string into. No memory space has been allocated to it, so what happens? Perhaps you should try declaring it as an array of a fixed size instead.

There may be other issues, but this is a starting point.

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