init

24/11/length.cpp

@@ -0,0 +1,38 @@
+#include "tree.c"
+
+TreeNode* findLCA(TreeNode* root, int node1, int node2) {
+    if (root == NULL || root->val == node1 || root->val == node2) {
+        return root;
+    }
+
+    TreeNode* left = findLCA(root->left, node1, node2);
+    TreeNode* right = findLCA(root->right, node1, node2);
+
+    if (left != NULL && right != NULL) {
+        return root;
+    }
+
+    return (left != NULL) ? left : right;
+}
+
+int findLevel(TreeNode* root, int val, int level) {
+    if (root == NULL) return -1;
+    if (root->val == val) return level;
+
+    int left = findLevel(root->left, val, level + 1);
+    if (left != -1) return left;
+
+    return findLevel(root->right, val, level + 1);
+}
+
+int nodeDistance(TreeNode *root, int node1, int node2) {
+    TreeNode* lca = findLCA(root, node1, node2);
+    if (lca == NULL) return -1;
+
+    int d1 = findLevel(lca, node1, 0);
+    int d2 = findLevel(lca, node2, 0);
+
+    if (d1 == -1 || d2 == -1) return -1;
+
+    return d1 + d2;
+}