Question

void addWord(char *word, bucket **bkt, int size)
{
    bucket *node, *auxNode;

    if(findWord(word, bkt[hash(word, size)]) == 1)
    {
            return;
    }

    node = (bucket*) malloc (sizeof(bucket));
    node->data = (char*) malloc (strlen(word) * sizeof(char));
    memset(node->data, 0, strlen(word));
    sprintf(node->data, "%s", word);

   if(*bkt == NULL)
       {
         node->next = NULL;
        *bkt = node;
    }
    else
    {
        auxNode = (bucket*) malloc (sizeof(bucket));
        auxNode = *bkt;
        while(auxNode->next != NULL)
        {
            auxNode = auxNode->next;
        }
        node->next = NULL;
        auxNode->next = node;
    }
}

int main(int argc, char **argv)
{
............
bkt = (bucket**) malloc (*sizeHash * sizeof(bucket*));
for(i = 0 ; i < (*sizeHash) ; i++)
{
    printf("%d\n", i);
    bkt[i] = NULL;
}
.........
    if(bkt[hash(pch, *sizeHash)] == NULL)
    {
        printf("NULL: %s -> %d\n",pch, hash(pch, *sizeHash));
        bkt[hash(pch, *sizeHash)] = NULL;
    }
    addWord(pch, &bkt[hash(pch, *sizeHash)], *sizeHash);

Every time enters in that if, that means that the node send is NULL; But after two inserts, the third although enters in that if, in addWord it arrives not NULL(i put a printf before findWord). I don’t understand why this happens. This is a hash table, hash() is djb2 of Dan Bernstein. Could somebody tell my why the NULL pointer isn’t send in addWord()?

Answer 1

Surely this:

    if(findWord(word, bkt[hash(word, size)]) == 1)

is supposed to be this:

    if(findWord(word, *bkt) == 1)

?

Remember that the bkt inside addWord is the &bkt[hash(pch, *sizeHash)] from main: it already points to the hash-entry for word.