给定一个二叉搜索树和一个关键字。检查给定密钥是否存在于BST中或不进行递归操作。
请参考二进制搜索树插入以进行递归搜索。
C++
// C++ program to demonstrate searching operation
// in binary search tree without recursion
#include
using namespace std;
struct Node {
int data;
struct Node *left, *right;
};
// Function to check the given key exist or not
bool iterativeSearch(struct Node* root, int key)
{
// Traverse untill root reaches to dead end
while (root != NULL) {
// pass right subtree as new tree
if (key > root->data)
root = root->right;
// pass left subtree as new tree
else if (key < root->data)
root = root->left;
else
return true; // if the key is found return 1
}
return false;
}
// A utility function to create a new BST Node
struct Node* newNode(int item)
{
struct Node* temp = new Node;
temp->data = item;
temp->left = temp->right = NULL;
return temp;
}
/* A utility function to insert a new Node with
given key in BST */
struct Node* insert(struct Node* Node, int data)
{
/* If the tree is empty, return a new Node */
if (Node == NULL)
return newNode(data);
/* Otherwise, recur down the tree */
if (data < Node->data)
Node->left = insert(Node->left, data);
else if (data > Node->data)
Node->right = insert(Node->right, data);
/* return the (unchanged) Node pointer */
return Node;
}
// Driver Program to test above functions
int main()
{
/* Let us create following BST
50
/ \
30 70
/ \ / \
20 40 60 80 */
struct Node* root = NULL;
root = insert(root, 50);
insert(root, 30);
insert(root, 20);
insert(root, 40);
insert(root, 70);
insert(root, 60);
insert(root, 80);
if (iterativeSearch(root, 15))
cout << "Yes";
else
cout << "No";
return 0;
} Java
// Java program to demonstrate searching operation
// in binary search tree without recursion
import java.util.*;
class GFG {
static class Node {
int data;
Node left, right;
};
// Function to check the given key exist or not
static boolean iterativeSearch(Node root, int key)
{
// Traverse untill root reaches to dead end
while (root != null) {
// pass right subtree as new tree
if (key > root.data)
root = root.right;
// pass left subtree as new tree
else if (key < root.data)
root = root.left;
else
return true; // if the key is found return 1
}
return false;
}
// A utility function to create a new BST Node
static Node newNode(int item)
{
Node temp = new Node();
temp.data = item;
temp.left = temp.right = null;
return temp;
}
/* A utility function to insert a new Node with
given key in BST */
static Node insert(Node Node, int data)
{
/* If the tree is empty, return a new Node */
if (Node == null)
return newNode(data);
/* Otherwise, recur down the tree */
if (data < Node.data)
Node.left = insert(Node.left, data);
else if (data > Node.data)
Node.right = insert(Node.right, data);
/* return the (unchanged) Node pointer */
return Node;
}
// Driver code
public static void main(String args[])
{
/* Let us create following BST
50
/ \
30 70
/ \ / \
20 40 60 80 */
Node root = null;
root = insert(root, 50);
insert(root, 30);
insert(root, 20);
insert(root, 40);
insert(root, 70);
insert(root, 60);
insert(root, 80);
if (iterativeSearch(root, 15))
System.out.println("YES");
else
System.out.println("NO");
}
}
// This code is contributed by Arnab KunduPython3
# Python program to demonstrate searching operation
# in binary search tree without recursion
class newNode:
# Constructor to create a new node
def __init__(self, data):
self.data = data
self.left = None
self.right = None
# Function to check the given
# key exist or not
def iterativeSearch(root, key):
# Traverse untill root reaches
# to dead end
while root != None:
# pass right subtree as new tree
if key > root.data:
root = root.right
# pass left subtree as new tree
elif key < root.data:
root = root.left
else:
return True # if the key is found return 1
return False
# A utility function to insert a
# new Node with given key in BST
def insert(Node, data):
# If the tree is empty, return
# a new Node
if Node == None:
return newNode(data)
# Otherwise, recur down the tree
if data < Node.data:
Node.left = insert(Node.left, data)
elif data > Node.data:
Node.right = insert(Node.right, data)
# return the (unchanged) Node pointer
return Node
# Driver Code
if __name__ == '__main__':
# Let us create following BST
# 50
# 30 70
# / \ / \
# 20 40 60 80
root = None
root = insert(root, 50)
insert(root, 30)
insert(root, 20)
insert(root, 40)
insert(root, 70)
insert(root, 60)
insert(root, 80)
if iterativeSearch(root, 15):
print("Yes")
else:
print("No")
# This code is contributed by PranchalKC#
// C# program to demonstrate searching operation
// in binary search tree without recursion
using System;
class GFG {
public class Node {
public int data;
public Node left, right;
};
// Function to check the given key exist or not
static bool iterativeSearch(Node root, int key)
{
// Traverse untill root reaches to dead end
while (root != null) {
// pass right subtree as new tree
if (key > root.data)
root = root.right;
// pass left subtree as new tree
else if (key < root.data)
root = root.left;
else
return true; // if the key is found return 1
}
return false;
}
// A utility function to create a new BST Node
static Node newNode(int item)
{
Node temp = new Node();
temp.data = item;
temp.left = temp.right = null;
return temp;
}
/* A utility function to insert a new Node with
given key in BST */
static Node insert(Node Node, int data)
{
/* If the tree is empty, return a new Node */
if (Node == null)
return newNode(data);
/* Otherwise, recur down the tree */
if (data < Node.data)
Node.left = insert(Node.left, data);
else if (data > Node.data)
Node.right = insert(Node.right, data);
/* return the (unchanged) Node pointer */
return Node;
}
// Driver code
public static void Main(String[] args)
{
/* Let us create following BST
50
/ \
30 70
/ \ / \
20 40 60 80 */
Node root = null;
root = insert(root, 50);
insert(root, 30);
insert(root, 20);
insert(root, 40);
insert(root, 70);
insert(root, 60);
insert(root, 80);
if (iterativeSearch(root, 15))
Console.WriteLine("YES");
else
Console.WriteLine("NO");
}
}
// This code has been contributed by 29AjayKumar输出：
No