求BST中第K大的元素

#include
using namespace std;//BST Node
struct Node{int data;Node *lchild;Node *rchild;void Init(int d, Node *l, Node *r){data &＃61; d; lchild &＃61; l; rchild &＃61; r;}
};void LinkNode(Node* pRoot, Node *pLeft, Node *pRight){pRoot->lchild &＃61; pLeft;pRoot->rchild &＃61; pRight;
}Node *FindKthLargestCore(Node *pRoot, int k, int &counter){if (!pRoot || k<1)//invalid input detection & recursion boundaryreturn NULL;Node *p &＃61; FindKthLargestCore(pRoot->rchild, k, counter);if (p)return p;counter&＃43;&＃43;;if (k&＃61;&＃61;counter)//another recursion boundaryreturn pRoot;Node *q &＃61; FindKthLargestCore(pRoot->lchild, k, counter);if (q)return q;return NULL;
}Node *FindKthLargest(Node *pRoot, int k){int counter &＃61; 0;//count of nodes already traversedreturn FindKthLargestCore(pRoot, k, counter);
}int main()
{Node *pNode &＃61; new Node[8];pNode[0].Init(4, NULL, NULL);pNode[1].Init(2, NULL, NULL);pNode[2].Init(6, NULL, NULL);pNode[3].Init(1, NULL, NULL);pNode[4].Init(3, NULL, NULL);pNode[5].Init(5, NULL, NULL);pNode[6].Init(7, NULL, NULL);pNode[7].Init(0, NULL, NULL);LinkNode(&pNode[0], &pNode[1], &pNode[2]);LinkNode(&pNode[1], &pNode[3], &pNode[4]);LinkNode(&pNode[2], &pNode[5], &pNode[6]);LinkNode(&pNode[3], &pNode[7], NULL);for (int k &＃61; 1; k <&＃61; 12; k&＃43;&＃43;){Node *pNodeKth &＃61; FindKthLargest(pNode, k);if (pNodeKth)cout<<"The "<"th Element is : "<data<<endl;elsecout<<"The "<"th Element does not exist!"<<endl;}delete []pNode;pNode &＃61; NULL;return 0;
}