用于检查二叉树是否为BST的C ++程序
二进制搜索树是一种二进制树数据结构,其中我们具有3个属性-
节点的二分搜索树的左侧子树仅包含键小于节点键的节点。
二叉搜索树节点的右子树仅包含键大于该节点的键的节点。
子树的左侧和右侧也必须都是二叉搜索树。
算法
Begin function BSTUtill() If node is equals to NULL then Return 1. If data of node is less than minimum or greater than maximum data then Return 0. Traverse left and right sub-trees recursively. End.
范例程式码
#include <iostream> #include <cstdlib> #include <climits> using namespace std; struct n { int d; n* l; n* r; }; int BSTUtil(n* node, int min, int max); int isBST(n* node) { return(BSTUtil(node, INT_MIN, INT_MAX)); } int BSTUtil(struct n* node, int min, int max) { if (node==NULL) return 1; if (node->d < min || node->d > max) return 0; return BSTUtil(node->l, min, node->d - 1) && BSTUtil(node->r, node->d + 1, max); } n* newN(int d) { n* nod = new n; nod->d = d; nod->l = NULL; nod->r = NULL; return nod; } int main() { n *root = newN(7); root->l = newN(6); root->r = newN(10); root->l->l = newN(2); root->l->r = newN(4); if (isBST(root)) cout<<"The Given Binary Tree is a BST"<<endl; else cout<<"The Given Binary Tree is not a BST"<<endl; n *root1 = newN(10); root1->l = newN(6); root1->r = newN(11); root1->l->l = newN(2); root1->l->r = newN(7); if (isBST(root1)) cout<<"The Given Binary Tree is a BST"<<endl; else cout<<"The Given Binary Tree is not a BST"<<endl; return 0; }
输出结果
The Given Binary Tree is not a BST The Given Binary Tree is a BST