Add C++ code for the chapter binary tree.

codes/cpp/chapter_tree/binary_tree.cpp

@@ -6,3 +6,35 @@
 
 #include "../include/include.hpp"
 
+
+/* Driver Code */
+int main() {
+    /* 初始化二叉树 */
+    // 初始化结点
+    TreeNode* n1 = new TreeNode(1);
+    TreeNode* n2 = new TreeNode(2);
+    TreeNode* n3 = new TreeNode(3);
+    TreeNode* n4 = new TreeNode(4);
+    TreeNode* n5 = new TreeNode(5);
+    // 构建引用指向（即指针）
+    n1->left = n2;
+    n1->right = n3;
+    n2->left = n4;
+    n2->right = n5;
+    cout << endl << "初始化二叉树\n" << endl;
+    PrintUtil::printTree(n1);
+
+    /* 插入与删除结点 */
+    TreeNode* P = new TreeNode(0);
+    // 在 n1 -> n2 中间插入结点 P
+    n1->left = P;
+    P->left = n2;
+    cout << endl << "插入结点 P 后\n" << endl;
+    PrintUtil::printTree(n1);
+    // 删除结点 P
+    n1->left = n2;
+    cout << endl << "删除结点 P 后\n" << endl;
+    PrintUtil::printTree(n1);
+
+    return 0;
+}