Added Count Good Nodes in Binary Tree

CMakeLists.txt

@@ -1338,4 +1338,15 @@ add_executable(Leaf-SimilarTrees
 target_link_libraries(
         Leaf-SimilarTrees
         GTest::gtest_main
+)
+
+# Count Good Nodes in Binary Tree
+add_executable(CountGoodNodesInBinaryTree
+        Medium/CountGoodNodesInBinaryTree/include/solution.hpp
+        Medium/CountGoodNodesInBinaryTree/tests/test.cpp
+)
+
+target_link_libraries(
+        CountGoodNodesInBinaryTree
+        GTest::gtest_main
 )

Medium/CountGoodNodesInBinaryTree/include/solution.hpp

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <vector>
+#include <iostream>
+#include <algorithm>
+#include <gtest/gtest.h>
+
+struct TreeNode {
+    const int32_t value;
+    TreeNode *left;
+    TreeNode *right;
+    explicit TreeNode(const int32_t value) :
+        value(value), left(nullptr), right(nullptr) { }
+};
+
+class Solution {
+public:
+    static auto good_nodes(TreeNode *root) -> size_t {
+        std::function<void(TreeNode*, int32_t)> preorder =
+                [&](TreeNode *node, int32_t curr_max) -> void {
+            if (node == nullptr) return;
+            if (node->value >= curr_max) {
+                ++_count;
+                curr_max = node->value;
+            }
+            preorder(node->left, curr_max);
+            preorder(node->right, curr_max);
+        };
+
+        preorder(root, root->value);
+        return _count;
+    }
+
+private:
+    static size_t _count;
+};

Medium/CountGoodNodesInBinaryTree/tests/test.cpp

@@ -0,0 +1,14 @@
+#include "../include/solution.hpp"
+
+auto main() -> int {
+    auto *root = new TreeNode(3);
+    root->left = new TreeNode(1);
+    root->left->left = new TreeNode(3);
+    root->right = new TreeNode(4);
+    root->right->right = new TreeNode(5);
+    root->right->left = new TreeNode(1);
+
+    std::cout << Solution::good_nodes(root);
+
+    return 0;
+}