1 files changed, 40 insertions, 0 deletions
diff --git a/comp2521/tf_idf/invertedIndexTree.c b/comp2521/tf_idf/invertedIndexTree.c
new file mode 100644
index 0000000..b66d6a8
--- /dev/null
+++ b/comp2521/tf_idf/invertedIndexTree.c
@@ -0,0 +1,40 @@
+#include "invertedIndexTree.h"
+
+// Returns a newly malloc'ed inverted index node, fields initialised to zero
+// except for word.
+struct InvertedIndexNode *createInvertedIndexNode(char *const word) {
+    struct InvertedIndexNode *ret = calloc(1, sizeof(struct InvertedIndexNode));
+    ret->word = word;
+    return ret;
+}
+
+// Inserts to a FileListNode BST. Uses strcmp to determine priority, with
+// negative values moving into the left and positive values into the right.
+struct InvertedIndexNode *
+insertInvertedIndexNode(struct InvertedIndexNode *node, char *const word) {
+    if (node == NULL) {
+        return createInvertedIndexNode(word);
+    }
+
+    const int comparison = strcmp(word, node->word);
+    if (comparison < 0) {
+        node->left = insertInvertedIndexNode(node->left, word);
+    }
+    if (comparison > 0) {
+        node->right = insertInvertedIndexNode(node->right, word);
+    }
+    return node;
+}
+
+// Searches for an invertedIndexNode via a string.
+struct InvertedIndexNode *
+searchInvertedIndexNode(struct InvertedIndexNode *head, char *const word) {
+    int comparison = strcmp(word, head->word);
+    if (head == NULL || !comparison) {
+        return head;
+    }
+    if (comparison < 0) {
+        return searchInvertedIndexNode(head->left, word);
+    }
+    return searchInvertedIndexNode(head->right, word);
+}