LCP 67

include/solution/lcp_67.h

@@ -0,0 +1,16 @@
+//
+// Created by xfj12 on 2025/3/25.
+//
+
+#ifndef LCP_67_H
+#define LCP_67_H
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+#include <TreeNode.h>
+    struct TreeNode *expandBinaryTree(struct TreeNode *root);
+#ifdef __cplusplus
+}
+#endif
+#endif // LCP_67_H

src/lcp_67.c

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+//
+// Created by xfj12 on 2025/3/25.
+//
+#include <solution/lcp_67.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+void inorder(struct TreeNode *root)
+{
+    if (root == NULL)
+        return;
+    inorder(root->left);
+    if (root->left != NULL && root->val != -1)
+    {
+        struct TreeNode *p = root->left;
+        root->left = malloc(sizeof(struct TreeNode));
+        root->left->left = p;
+        root->left->right = NULL;
+        root->left->val = -1;
+    }
+
+    if (root->right != NULL && root->val != -1)
+    {
+        struct TreeNode *p = root->right;
+        root->right = malloc(sizeof(struct TreeNode));
+        root->right->right = p;
+        root->right->left = NULL;
+        root->right->val = -1;
+    }
+    inorder(root->right);
+}
+
+struct TreeNode *expandBinaryTree(struct TreeNode *root)
+{
+    inorder(root);
+    return root;
+}

tests/test_lcp_67.cpp

@@ -0,0 +1,54 @@
+//
+// Created by xfj12 on 2025/3/25.
+//
+#include <gtest/gtest.h>
+#include <queue>
+#include <solution/lcp_67.h>
+
+bool areTreesEqual(TreeNode *t1, TreeNode *t2)
+{
+    if (!t1 && !t2)
+        return true;
+    if (!t1 || !t2)
+        return false;
+    return (t1->val == t2->val) && areTreesEqual(t1->left, t2->left) && areTreesEqual(t1->right, t2->right);
+}
+
+TreeNode *buildTree(const std::vector<int> &values)
+{
+    if (values.empty())
+        return nullptr;
+    std::vector<TreeNode *> nodes;
+    for (int val : values)
+    {
+        nodes.push_back(val == INT_MIN ? nullptr : new TreeNode{val, nullptr, nullptr});
+    }
+    for (size_t i = 0, j = 1; j < nodes.size(); ++i)
+    {
+        if (nodes[i])
+        {
+            if (j < nodes.size())
+                nodes[i]->left = nodes[j++];
+            if (j < nodes.size())
+                nodes[i]->right = nodes[j++];
+        }
+    }
+    return nodes[0];
+}
+
+TEST(ExpandBinaryTreeTest, Test1)
+{
+    TreeNode *root = buildTree({7, 5, 6});
+    TreeNode *expanded = expandBinaryTree(root);
+    TreeNode *expected = buildTree({7, -1, -1, 5, INT_MIN, INT_MIN, 6});
+    EXPECT_TRUE(areTreesEqual(expanded, expected));
+}
+
+TEST(ExpandBinaryTreeTest, Test2)
+{
+    TreeNode *root = buildTree({3, 1, 7, 3, 8, INT_MIN, 4});
+    TreeNode *expanded = expandBinaryTree(root);
+    TreeNode *expected =
+        buildTree({3, -1, -1, 1, INT_MIN, INT_MIN, 7, -1, -1, INT_MIN, -1, 3, INT_MIN, INT_MIN, 8, INT_MIN, 4});
+    EXPECT_TRUE(areTreesEqual(expanded, expected));
+}