关于二叉树（中）

TreeNode* traversal(vector<int>& preorder, int preBegin, int preEnd, vector<int>& inorder, int inBegin, int inEnd) {
		if (preBegin == preEnd) return nullptr;

		//找到当前根节点
		int rootValue = preorder[preBegin];
		TreeNode* node = new TreeNode(rootValue);

		//判断是否为叶子节点
		if (preEnd - preBegin == 1) return node;

		//在中序遍历中找到对应节点
		int divideNode;
		for (divideNode = 0; divideNode <= inEnd; ++divideNode)
			if (inorder[divideNode] == rootValue)
				break;

    //左开右闭区间分割 [)
		//分割中序数组
		int leftInorderBegin = inBegin;
		int leftInorderEnd = divideNode;

		int rightInorderBegin = divideNode + 1;
		int rightInorderEnd = inEnd;

		//分割前序数组
		int leftPreorderBegin = preBegin + 1;
		int leftPreorderEnd = preBegin + (leftInorderEnd - leftInorderBegin) + 1;

		int rightPreorderBegin = leftPreorderEnd;
		int rightPreorderEnd = preEnd;

    //递归
    node->left = traversal(preorder, leftPreorderBegin, leftPreorderEnd, inorder, leftInorderBegin, leftInorderEnd);
		node->right = traversal(preorder, rightPreorderBegin, rightPreorderEnd, inorder, rightInorderBegin, rightInorderEnd);

		return node;
    }

TreeNode* traversal(vector<int>& postorder, int postorderBegin, int postorderEnd, vector<int>& inorder, int inBegin, int inEnd) {
		if (postorderBegin == postorderEnd) return nullptr;

		//找到当前根节点
		int rootValue = postorder[postorderEnd - 1];
		TreeNode* node = new TreeNode(rootValue);

		//判断是否为叶子节点
		if (postorderEnd - postorderBegin == 1) return node;

		//在中序遍历中找到对应节点
		int divideNode;
		for (divideNode = 0; divideNode <= inEnd; ++divideNode)
			if (inorder[divideNode] == rootValue)
				break;

		//左开右闭区间分割 [)
		//分割中序数组
		int leftInorderBegin = inBegin;
		int leftInorderEnd = divideNode;

		int rightInorderBegin = divideNode + 1;
		int rightInorderEnd = inEnd;

		//分割后序数组
		int leftpostorderBegin = postorderBegin;
		int leftpostorderEnd = postorderBegin + (leftInorderEnd - leftInorderBegin);

		int rightpostorderBegin = leftpostorderEnd;
		int rightpostorderEnd = postorderEnd - 1;

		//递归
		node->left = traversal(postorder, leftpostorderBegin, leftpostorderEnd, inorder, leftInorderBegin, leftInorderEnd);
		node->right = traversal(postorder, rightpostorderBegin, rightpostorderEnd, inorder, rightInorderBegin, rightInorderEnd);

		return node;
	}

void printTree(TreeNode* root, int level = 0, int indent = 4) {
    if (!root) return;

    printTree(root->right, level + 1, indent);
    if (level != 0) {
        cout << setw(level * indent) << " ";
    }
    cout << root->val << endl;
    printTree(root->left, level + 1, indent);
}