Trie Implementation in C

Algorithm

Hello, I learned Trie in my CS1 class, and implemented it. So, let me share my code! My struct for trie looks like this

struct trie {
	int isWord;
	struct trie* nextLetter[26];
};

And, my code for creating single node, and inserting a word looks like this.

struct trie* createSingleTrie() {
	struct trie* temp = malloc(sizeof(struct trie));
	temp->isWord = 0;

	int i;
	for (i = 0; i < 26; i++) {
		temp->nextLetter[i] = NULL;
	}
	return temp;
}

void insertWord(struct trie* dictionary, char word[], int index, int wordLength) {
	if (index == wordLength) {
		dictionary->isWord = 1;
		return;
	}
	if (dictionary->nextLetter[word[index] - 'a'] == NULL) {
		dictionary->nextLetter[word[index] - 'a'] = createSingleTrie();
	}
	insertWord(dictionary->nextLetter[word[index] - 'a'], word, index + 1, wordLength);
}

int isInDictionary(struct trie* dictionary, char word[], int index, int length) {
	if (dictionary == NULL) {
		return 0;
	}
	if (index == length) {
		return dictionary->isWord;
	}
	return isInDictionary(dictionary->nextLetter[word[index] - 'a'], word, index + 1, length);
}

It is a bit long to put all codes here, so check out my Github Gist!