Question

对于类，我必须创建一个binaryTree，我似乎无法让insert方法正常工作。

预期结果：

first: tree is not empty
        no of nodes    = 15
        height of tree =  5

The elements of 'first' in inorder:
        -11 8 -3 12 -1 -9 -5 2 16 10 6 -13 4 14 -7
The elements of 'first' in preorder:
        2 -1 -3 8 -11 12 -5 -9 4 6 10 16 -13 -7 14
The elements of 'first' in postorder:
        -11 8 12 -3 -9 -5 -1 16 10 -13 6 14 -7 4 2

second: tree is not empty
        no of nodes    =  9
        height of tree =  4

The elements of 'second' in inorder:
        7 3.25 0.75 -7.75 -0.5 -11.5 4.5 -4 8.25
The elements of 'second' in preorder:
        -0.5 0.75 3.25 7 -7.75 -4 4.5 -11.5 8.25
The elements of 'second' in postorder:
        7 3.25 -7.75 0.75 -11.5 4.5 8.25 -4 -0.5

third: tree is not empty
        no of nodes    =  7
        height of tree =  4

The elements of 'third' in inorder:
        objects. list is string This of a
The elements of 'third' in preorder:
        This is list objects. string a of
The elements of 'third' in postorder:
        objects. list string is of a This

我的结果：

first: tree is not empty
       no of nodes    = 15
       height of tree = 4
The elements of 'first' in inorder:
-9 -5 4 16 -1 -13 10 -7 2 14 8 6 -3 -11 12
The elements of 'first' in preorder:
2 -1 4 -5 -9 16 -7 10 -13 -3 6 8 14 12 -11
The elements of 'first' in postorder:
-9 -5 16 4 -13 10 -7 -1 14 8 6 -11 12 -3 2
second: tree is not empty
       no of nodes    = 9
       height of tree = 3
The elements of 'second' in inorder:
-7.75 -4 0.75 -11.5 8.25 -0.5 7 4.5 3.25
The elements of 'second' in preorder:
-0.5 0.75 -4 -7.75 8.25 -11.5 3.25 4.5 7
The elements of 'second' in postorder:
-7.75 -4 -11.5 8.25 0.75 7 4.5 3.25 -0.5
third: tree is not empty
       no of nodes    = 7
       height of tree = 3
The elements of 'third' in inorder:
string a is This objects. of list
The elements of 'third' in preorder:
This is a string list of objects.
The elements of 'third' in postorder:
string a is objects. of list This

代码：

template <class T>
void binTree<T>::insert(binTreeNode < T >*& node, const T& data) {
        if(node == NULL) {
                root = new binTreeNode<T>(data, NULL, NULL);
                return;
        }

        binTreeNode<T>* ptr1 = node;
        binTreeNode<T>* ptr2 = node;
        bool placeRight = 0;
        while(ptr1 != NULL) {
                ptr2 = ptr1;
                if(height(ptr1->left) > height(ptr1->right)) {
                        placeRight = true;
                        ptr1 = ptr1->right;
                } else if (height(ptr1->right) > height(ptr1->left)) {
                        placeRight = false;
                        ptr1 = ptr1->left;
                } else {
                        placeRight = false;
                        ptr1 = ptr1->left;
                }
        }

        if(placeRight) {
                ptr2->right = new binTreeNode<T>(data, NULL, NULL);
        } else {
                ptr2->left = new binTreeNode<T>(data, NULL, NULL);
        }
}

驱动程序：

const vector<int> A { 1, -2, 3, -4, 5, -6, 7, -8, 9, -10, 11, -12, 13, -14, 15 };
const vector<float> B { 0.5, 1.75, -3, 4.25, 5.50, -6.75, 8, 9.25, -10.5 };
const vector<string> C { "This", "is", "a", "list", "of", "string", "objects." };
int main() {
        binTree<int> intTree = binTree<int>();
        binTree<float> floatTree = binTree<float>();
        binTree<string> strTree = binTree<string>();

        for (std::vector<int>::const_iterator it = A.begin() ; it != A.end(); ++it) {
                intTree.insert(*it);
        }
        intTree.preorder(increase);
        cout << "first: ";
        header(intTree);

        inorder(intTree, "first");
        preorder(intTree, "first");
        postOrder(intTree, "first");
}

显示结果的功能:(应该是正确的）

template <class T>
void binTree<T>::inorder(binTreeNode < T >* node, void (*f)(T&))
{
        if (node == NULL) {
                return;
        }
        inorder(node->left,f);
        f(node->data);
        inorder(node->right,f);
}


template <class T>
void binTree<T>::preorder(binTreeNode < T >* node, void(*f)(T&))
{
        if (node == NULL) {
                return;
        }
        f(node->data);
        preorder(node->left, f);
        preorder(node->right, f);
}


template <class T>
void binTree<T>::postorder(binTreeNode < T >* node, void(*f)(T&))
{
        if (node == NULL) {
                return;
        }
        postorder(node->left, f);
        postorder(node->right, f);
        f(node->data);
}

template <class T>
    int binTree<T>::height(binTreeNode <T>* node) const {
    if (node == NULL || ((node->left == NULL) && (node->right == NULL))) {
            return 0;
    }

    int leftSide = height(node->left);
    int rightSide = height(node->right);

    if (leftSide > rightSide) {
            return leftSide + 1;
    } else {
            return rightSide + 1;
    }
}

Answer 1

你的错误是你的身高法。如果您的节点不为null但没有子节点，则返回零。你应该回来1。

在身高法中更改此条件：

if (node == NULL || ((node->left == NULL) && (node->right == NULL))) {
    return 0;
}

为：

if (node == NULL) {
    return 0;
}

Answer 2

您的矢量A的符号似乎是向后的。您有1,-2,3,-4,...，但正确的解决方案有-1,2,-3,4,...。同样，您B是

const vector<float> B { 0.5, 1.75, -3, 4.25, 5.50, -6.75, 8, 9.25, -10.5 };

将此与您所说的我们期望的元素进行比较：

7, 3.25, 0.75, -7.75, -0.5, -11.5, 4.5, -4, 8.25

这些看起来甚至差不多相同。

某处有转录错误？

Answer 3

你的身高（）功能是什么？

我认为你误解了BST的定义：

A. the value of the left child is smaller than the value of root node.

B. the value of the right child is bigger than the value of root node.

C. his left child tree and right child tree are also a BST.

但是通过你的代码：

while(ptr1 != NULL) {
            ptr2 = ptr1;
            if(height(ptr1->left) > height(ptr1->right)) {
                    placeRight = true;
                    ptr1 = ptr1->right;
            } else if (height(ptr1->right) > height(ptr1->left)) {
                    placeRight = false;
                    ptr1 = ptr1->left;
            } else {
                    placeRight = false;
                    ptr1 = ptr1->left;
            }
    }

您只需比较节点的高度，而不是比较节点的实际值。

二进制树插入方法

3 个答案: