Added Path Sum

CMakeLists.txt

@@ -810,4 +810,15 @@ add_executable(ConstructBinaryTreeFromInorderAndPostorderTraversal
 target_link_libraries(
         ConstructBinaryTreeFromInorderAndPostorderTraversal
         GTest::gtest_main
+)
+
+# Path Sum
+add_executable(PathSum
+        Easy/PathSum/include/solution.hpp
+        Easy/PathSum/tests/test.cpp
+)
+
+target_link_libraries(
+        PathSum
+        GTest::gtest_main
 )

Easy/PathSum/include/solution.hpp

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <stack>
+#include <vector>
+#include <iostream>
+#include <algorithm>
+#include <gtest/gtest.h>
+
+struct TreeNode {
+    const int32_t value;
+    TreeNode *left;
+    TreeNode *right;
+    explicit TreeNode(int32_t value) :
+            value(value), left(nullptr), right(nullptr) { }
+};
+
+class Solution {
+public:
+    static auto has_path_sum(TreeNode *root,
+                             const int32_t target) -> bool {
+        if (root == nullptr) return false;
+
+        std::stack<TreeNode*> node_stack;
+        std::stack<int32_t> sum_stack;
+
+        node_stack.push(root);
+        sum_stack.push(target - root->value);
+
+        while (!node_stack.empty()) {
+            TreeNode *current_node = node_stack.top();
+            node_stack.pop();
+            int32_t current_sum = sum_stack.top();
+            sum_stack.pop();
+
+            if (!current_node->left && !current_node->right && current_sum == 0) {
+                return true;
+            } if (current_node->left) {
+                node_stack.push(current_node->left);
+                sum_stack.push(current_sum -
+                    current_node->left->value);
+            } if (current_node->right) {
+                node_stack.push(current_node->right);
+                sum_stack.push(current_sum -
+                    current_node->right->value);
+            }
+        }
+
+        return false;
+    }
+};

Easy/PathSum/tests/test.cpp

@@ -0,0 +1,17 @@
+#include "../include/solution.hpp"
+
+auto main() -> int {
+    auto *root = new TreeNode(5);
+    root->left = new TreeNode(4);
+    root->left->left = new TreeNode(11);
+    root->left->left->left = new TreeNode(7);
+    root->left->left->right = new TreeNode(2);
+    root->right = new TreeNode(8);
+    root->right->left = new TreeNode(13);
+    root->right->right = new TreeNode(4);
+    root->right->right->right = new TreeNode(1);
+
+    std::cout << std::boolalpha << Solution::has_path_sum(root, 22);
+
+    return 0;
+}