diff --git a/bintree.c b/bintree.c
index 5cf82a9..2927e04 100644
--- a/bintree.c
+++ b/bintree.c
@@ -12,7 +12,26 @@
 // if isDuplicate is NULL, otherwise ignores duplicates and sets isDuplicate to 1 (or to 0 if a new entry is added).
 TreeNode *addToTree(TreeNode *root, const void *data, size_t dataSize, CompareFctType compareFct, int *isDuplicate)
 {
+    TreeNode newNode = {data, NULL, NULL};
+    
 
+    if(root == NULL)
+    {
+        return &newNode;
+    }
+
+    if (data < root->data)
+    {
+        root->left = addToTree(root->left, data, dataSize,compareFct, isDuplicate);
+    }
+    else if(data > root->data)
+    {
+       root->right = addToTree(root->right, data, dataSize,compareFct, isDuplicate);
+    }
+
+
+
+    return root;
 }
 
 // Iterates over the tree given by root. Follows the usage of strtok. If tree is NULL, the next entry of the last tree given is returned in ordering direction.
@@ -32,5 +51,12 @@ void clearTree(TreeNode *root)
 // Returns the number of entries in the tree given by root.
 unsigned int treeSize(const TreeNode *root)
 {
+    int counter = 0;
 
+    if(root != NULL)
+    {
+       treeSize(root->left);
+       counter++;
+       treeSize(root->right);
+    }
 }
\ No newline at end of file
diff --git a/numbers.o b/numbers.o
deleted file mode 100644
index 507642a..0000000
Binary files a/numbers.o and /dev/null differ
diff --git a/runNumbersTest.exe b/runNumbersTest.exe
deleted file mode 100644
index e9feb27..0000000
Binary files a/runNumbersTest.exe and /dev/null differ