dictionary.c - shared from CS50 IDE

dictionary.c

/**
 * Returns true if word is in dictionary else false.
 */
bool check(const char *word)
{
    // starting the temp pointer at the root of the trie
    temp = root;
    // iterating over the length of the passed in words
    for (int i = 0; i < strlen(word) + 1 ; i ++)
    {   
        /** converting chars upper to lower to preserve case sensitivity
         * and skipping assignment to 0 or 10 to avoid conflict with
         * '/0' and '/n' chars
         */
         
        int x = word[i];
        
        if (isupper(word[i]))
        {
           x  = tolower(word[i]);
           x = x - 96;
           if (x == 10)
           {
               x = 27;
           }
           
        }
        else if (islower(word[i]))
        {
            x = word[i] - 96;
            if (x == 10)
            {
                x = 27;
            }
        }
        else if (word[i] == '\'')
        {
            x = 28;
        }
        
        // if corresponding node is NULL
        if (temp->paths[x] == NULL)
        {
            // check to see if we are at the end of our passed in word
            if (x == '\0')
            {   
                // if valid word this is a word in dictionary
                if (temp->validword == true)
                {
                    return true;
                }
                //otherwise not a word in dictionary
                else
                {
                    return false;
                }
            }
            // otherwise we're in the middle of a word and can't proceed
            else
            {
                // not a word
                return false;
            }
        }
        
        // the corresponding node is open
        else if (temp->paths[x] != NULL)
        {   
            //proceed to the next node
            temp = temp -> paths[x]; 
        }   
    }
    
    return false;

}