C++ 二叉搜索树getHeight（）函数_C++_Tdd_Binary Search Tree

C++ 二叉搜索树getHeight（）函数

c++

C++ 二叉搜索树getHeight（）函数,c++,tdd,binary-search-tree,C++,Tdd,Binary Search Tree,我正在尝试编写一个返回BST高度的函数。我正在使用测试驱动开发编写代码，但不幸的是，它没有通过我的测试，我不知道为什么我通过了考试的第0、1和2部分，但第3部分不及格。非常感谢您能帮助我找出代码的错误。谢谢大家! 以下是我代码的一些相关摘录： BST.cpp unsigned BST::Node::getHeight() const{ unsigned leftSide = 0; if(myLeft != NULL){ myLeft->getHeight(

我正在尝试编写一个返回BST高度的函数。我正在使用测试驱动开发编写代码，但不幸的是，它没有通过我的测试，我不知道为什么

我通过了考试的第0、1和2部分，但第3部分不及格。非常感谢您能帮助我找出代码的错误。谢谢大家!

以下是我代码的一些相关摘录：

BST.cpp

unsigned BST::Node::getHeight() const{
    unsigned leftSide = 0;
    if(myLeft != NULL){
        myLeft->getHeight();
    }
    unsigned rightSide = 0;
    if(myRight != NULL){
        myRight->getHeight();
    }
    if(leftSide > rightSide){
        return leftSide++;
    } else{
        return rightSide++;
    }
}

unsigned BST::getHeight() const{
    if(myNumItems == 0){
        return 0;
    } else if(myNumItems == 1){
        return 1;
    } else if(myNumItems == 2){
        return 2;
    } else {
        return myRoot->getHeight();
    }
}

void BST_Tester::testGetHeight() {
cout << "Testing getHeight()..." << flush;
BST bst;
// empty
assert( bst.getHeight() == 0 );
cout << " 0 " << flush;
// balanced
bst.insert(44);
assert( bst.getHeight() == 1 );
cout << " 1 " << flush;
bst.insert(22);
assert( bst.getHeight() == 2 );
cout << " 2 " << flush;
bst.insert(66);
assert( bst.getHeight() == 2 );
cout << " 3 " << flush;
bst.insert(77);
assert( bst.getHeight() == 3 );
cout << " 4a " << flush;
bst.insert(55);
assert( bst.getHeight() == 3 );
cout << " 4b " << flush;
bst.insert(33);
assert( bst.getHeight() == 3 );
cout << " 4c " << flush;
bst.insert(11);
assert( bst.getHeight() == 3 );
cout << " 4d " << flush;
bst.insert(88);
assert( bst.getHeight() == 4 );
cout << " 4e " << flush;
// chained ascending
  BST bst2a;
  bst2a.insert(11);
  bst2a.insert(22);
  bst2a.insert(33);
  bst2a.insert(44);
  bst2a.insert(55);
  bst2a.insert(66);
  bst2a.insert(77);
  assert( bst2a.getHeight() == 7 );
  cout << " 5a " << flush;
// chained descending
  BST bst2b;
  bst2b.insert(77);
  bst2b.insert(66);
  bst2b.insert(55);
  bst2b.insert(44);
  bst2b.insert(33);
  bst2b.insert(22);
  bst2b.insert(11);
  assert( bst2b.getHeight() == 7 );
  cout << " 5b " << flush;
// four 4-node permutations
BST bst3;
bst3.insert(44);
assert( bst3.getHeight() == 1 );
  cout << " 6a " << flush;
bst3.insert(22);
assert( bst3.getHeight() == 2 );
  cout << " 6b " << flush;
bst3.insert(33);
assert( bst3.getHeight() == 3 );
  cout << " 6c " << flush;
bst3.insert(55);
assert( bst3.getHeight() == 3 );
  cout << " 6d " << flush;
BST bst4;
bst4.insert(44);
assert( bst4.getHeight() == 1 );
  cout << " 7a " << flush;
bst4.insert(33);
assert( bst4.getHeight() == 2 );
  cout << " 7b " << flush;
bst4.insert(22);
assert( bst4.getHeight() == 3 );
  cout << " 7c " << flush;
bst4.insert(55);
assert( bst4.getHeight() == 3 );
  cout << " 7d " << flush;
BST bst5;
bst5.insert(44);
assert( bst5.getHeight() == 1 );
  cout << " 8a " << flush;
bst5.insert(33);
assert( bst5.getHeight() == 2 );
  cout << " 8b " << flush;
bst5.insert(55);
assert( bst5.getHeight() == 2 );
  cout << " 8c " << flush;
bst5.insert(66);
assert( bst5.getHeight() == 3 );
  cout << " 8d " << flush;
BST bst6;
bst6.insert(44);
assert( bst6.getHeight() == 1 );
  cout << " 9a " << flush;
bst6.insert(33);
assert( bst6.getHeight() == 2 );
  cout << " 9b " << flush;
bst6.insert(66);
assert( bst6.getHeight() == 2 );
  cout << " 9c " << flush;
bst6.insert(55);
assert( bst6.getHeight() == 3 );
  cout << " 9d " << flush;
cout << " Passed!" << endl;
}

BST.h

class BST {
public:
    BST();
    virtual ~BST();
    unsigned getHeight() const;
private:
struct Node {
    Node(const Item& it);
        virtual ~Node();
        void insert(const Item& it);
        unsigned getHeight() const;

        Item myItem;
        Node* myLeft;
        Node* myRight;
};

Node* myRoot;
unsigned myNumItems;
friend class BST_Tester;
};

BST\U测试仪.cpp

unsigned BST::Node::getHeight() const{
    unsigned leftSide = 0;
    if(myLeft != NULL){
        myLeft->getHeight();
    }
    unsigned rightSide = 0;
    if(myRight != NULL){
        myRight->getHeight();
    }
    if(leftSide > rightSide){
        return leftSide++;
    } else{
        return rightSide++;
    }
}

unsigned BST::getHeight() const{
    if(myNumItems == 0){
        return 0;
    } else if(myNumItems == 1){
        return 1;
    } else if(myNumItems == 2){
        return 2;
    } else {
        return myRoot->getHeight();
    }
}

void BST_Tester::testGetHeight() {
cout << "Testing getHeight()..." << flush;
BST bst;
// empty
assert( bst.getHeight() == 0 );
cout << " 0 " << flush;
// balanced
bst.insert(44);
assert( bst.getHeight() == 1 );
cout << " 1 " << flush;
bst.insert(22);
assert( bst.getHeight() == 2 );
cout << " 2 " << flush;
bst.insert(66);
assert( bst.getHeight() == 2 );
cout << " 3 " << flush;
bst.insert(77);
assert( bst.getHeight() == 3 );
cout << " 4a " << flush;
bst.insert(55);
assert( bst.getHeight() == 3 );
cout << " 4b " << flush;
bst.insert(33);
assert( bst.getHeight() == 3 );
cout << " 4c " << flush;
bst.insert(11);
assert( bst.getHeight() == 3 );
cout << " 4d " << flush;
bst.insert(88);
assert( bst.getHeight() == 4 );
cout << " 4e " << flush;
// chained ascending
  BST bst2a;
  bst2a.insert(11);
  bst2a.insert(22);
  bst2a.insert(33);
  bst2a.insert(44);
  bst2a.insert(55);
  bst2a.insert(66);
  bst2a.insert(77);
  assert( bst2a.getHeight() == 7 );
  cout << " 5a " << flush;
// chained descending
  BST bst2b;
  bst2b.insert(77);
  bst2b.insert(66);
  bst2b.insert(55);
  bst2b.insert(44);
  bst2b.insert(33);
  bst2b.insert(22);
  bst2b.insert(11);
  assert( bst2b.getHeight() == 7 );
  cout << " 5b " << flush;
// four 4-node permutations
BST bst3;
bst3.insert(44);
assert( bst3.getHeight() == 1 );
  cout << " 6a " << flush;
bst3.insert(22);
assert( bst3.getHeight() == 2 );
  cout << " 6b " << flush;
bst3.insert(33);
assert( bst3.getHeight() == 3 );
  cout << " 6c " << flush;
bst3.insert(55);
assert( bst3.getHeight() == 3 );
  cout << " 6d " << flush;
BST bst4;
bst4.insert(44);
assert( bst4.getHeight() == 1 );
  cout << " 7a " << flush;
bst4.insert(33);
assert( bst4.getHeight() == 2 );
  cout << " 7b " << flush;
bst4.insert(22);
assert( bst4.getHeight() == 3 );
  cout << " 7c " << flush;
bst4.insert(55);
assert( bst4.getHeight() == 3 );
  cout << " 7d " << flush;
BST bst5;
bst5.insert(44);
assert( bst5.getHeight() == 1 );
  cout << " 8a " << flush;
bst5.insert(33);
assert( bst5.getHeight() == 2 );
  cout << " 8b " << flush;
bst5.insert(55);
assert( bst5.getHeight() == 2 );
  cout << " 8c " << flush;
bst5.insert(66);
assert( bst5.getHeight() == 3 );
  cout << " 8d " << flush;
BST bst6;
bst6.insert(44);
assert( bst6.getHeight() == 1 );
  cout << " 9a " << flush;
bst6.insert(33);
assert( bst6.getHeight() == 2 );
  cout << " 9b " << flush;
bst6.insert(66);
assert( bst6.getHeight() == 2 );
  cout << " 9c " << flush;
bst6.insert(55);
assert( bst6.getHeight() == 3 );
  cout << " 9d " << flush;
cout << " Passed!" << endl;
}

这只是将leftSide++翻转到leftSide++的问题。

放弃您的代码。试着这么做，伙计

int getHeight(tree *p)
{
   if (!p)
       return 0;

   int left = getHeight(p->left);
   int right = getHeight(p->right); 
   return max(left, right) +1;
}

如果有一个工具可以让你分步检查代码和变量……很抱歉，这段代码太糟糕了。很遗憾看到StackOverflow变得更加挑剔和判断，而不是有用。这不起作用。你的参数应该是一棵树，但你试图把p->left和p->right作为非树的参数。如果你好奇，我可以使用我的代码。有关我的解决方案，请参阅我编辑的文章。