Print all even nodes of Binary Search Tree
Given a binary search tree. The task is to print all even nodes of the binary search tree.
Examples:
Input : 5 / \ 3 7 / \ / \ 2 4 6 8 Output : 2 4 6 8 Input : 14 / \ 12 17 / \ / \ 8 13 16 19 Output : 8 12 14 16
Approach: Traverse the Binary Search tree and check if current node’s value is even. If yes then print it otherwise skip that node.
Below is the implementation of the above Approach:
C++
// C++ program to print all even node of BST #include <bits/stdc++.h> using namespace std; // create Tree struct Node { int key; struct Node *left, *right; }; // A utility function to create a new BST node Node* newNode( int item) { Node* temp = new Node; temp->key = item; temp->left = temp->right = NULL; return temp; } // A utility function to do inorder traversal of BST void inorder(Node* root) { if (root != NULL) { inorder(root->left); printf (root->key,end= " " ); inorder(root->right); } } /* A utility function to insert a new node with given key in BST */ Node* insert(Node* node, int key) { /* If the tree is empty, return a new node */ if (node == NULL) return newNode(key); /* Otherwise, recur down the tree */ if (key < node->key) node->left = insert(node->left, key); else node->right = insert(node->right, key); /* return the (unchanged) node pointer */ return node; } // Function to print all even nodes void evenNode(Node* root) { if (root != NULL) { evenNode(root->left); // if node is even then print it if (root->key % 2 == 0) printf ( "%d " , root->key); evenNode(root->right); } } // Driver Code int main() { /* Let us create following BST 5 / \ 3 7 / \ / \ 2 4 6 8 */ Node* root = NULL; root = insert(root, 5); root = insert(root, 3); root = insert(root, 2); root = insert(root, 4); root = insert(root, 7); root = insert(root, 6); root = insert(root, 8); evenNode(root); return 0; } |
Java
// Java program to print all even node of BST class GfG { // create Tree static class Node { int key; Node left, right; } // A utility function to create a new BST node static Node newNode( int item) { Node temp = new Node(); temp.key = item; temp.left = null ; temp.right = null ; return temp; } // A utility function to do inorder traversal of BST static void inorder(Node root) { if (root != null ) { inorder(root.left); System.out.print(root.key + " " ); inorder(root.right); } } /* A utility function to insert a new node with given key in BST */ static Node insert(Node node, int key) { /* If the tree is empty, return a new node */ if (node == null ) return newNode(key); /* Otherwise, recur down the tree */ if (key < node.key) node.left = insert(node.left, key); else node.right = insert(node.right, key); /* return the (unchanged) node pointer */ return node; } // Function to print all even nodes static void evenNode(Node root) { if (root != null ) { evenNode(root.left); // if node is even then print it if (root.key % 2 == 0 ) System.out.print(root.key + " " ); evenNode(root.right); } } // Driver Code public static void main(String[] args) { /* Let us create following BST 5 / \ 3 7 / \ / \ 2 4 6 8 */ Node root = null ; root = insert(root, 5 ); root = insert(root, 3 ); root = insert(root, 2 ); root = insert(root, 4 ); root = insert(root, 7 ); root = insert(root, 6 ); root = insert(root, 8 ); evenNode(root); } } |
Python3
# Python3 program to print all even node of BST # create Tree # to create a new BST node class newNode: # Construct to create a new node def __init__( self , key): self .key = key self .left = None self .right = None # A utility function to do inorder # traversal of BST def inorder(root) : if (root ! = None ): inorder(root.left) printf( "%d " , root.key) inorder(root.right) """ A utility function to insert a new node with given key in BST """ def insert(node, key): """ If the tree is empty, return a new node """ if (node = = None ): return newNode(key) """ Otherwise, recur down the tree """ if (key < node.key): node.left = insert(node.left, key) else : node.right = insert(node.right, key) """ return the (unchanged) node pointer """ return node # Function to print all even nodes def evenNode(root) : if (root ! = None ): evenNode(root.left) # if node is even then print it if (root.key % 2 = = 0 ): print (root.key, end = " " ) evenNode(root.right) # Driver Code if __name__ = = '__main__' : """ Let us create following BST 5 / \ 3 7 / \ / \ 2 4 6 8 """ root = None root = insert(root, 5 ) root = insert(root, 3 ) root = insert(root, 2 ) root = insert(root, 4 ) root = insert(root, 7 ) root = insert(root, 6 ) root = insert(root, 8 ) evenNode(root) # This code is contributed by # Shubham Singh(SHUBHAMSINGH10) |
C#
// C# program to print all even node of BST using System; class GfG { // create Tree class Node { public int key; public Node left, right; } // A utility function to // create a new BST node static Node newNode( int item) { Node temp = new Node(); temp.key = item; temp.left = null ; temp.right = null ; return temp; } // A utility function to do // inorder traversal of BST static void inorder(Node root) { if (root != null ) { inorder(root.left); Console.Write(root.key + " " ); inorder(root.right); } } /* A utility function to insert a new node with given key in BST */ static Node insert(Node node, int key) { /* If the tree is empty, return a new node */ if (node == null ) return newNode(key); /* Otherwise, recur down the tree */ if (key < node.key) node.left = insert(node.left, key); else node.right = insert(node.right, key); /* return the (unchanged) node pointer */ return node; } // Function to print all even nodes static void evenNode(Node root) { if (root != null ) { evenNode(root.left); // if node is even then print it if (root.key % 2 == 0) Console.Write(root.key + " " ); evenNode(root.right); } } // Driver Code public static void Main(String[] args) { /* Let us create following BST 5 / \ 3 7 / \ / \ 2 4 6 8 */ Node root = null ; root = insert(root, 5); root = insert(root, 3); root = insert(root, 2); root = insert(root, 4); root = insert(root, 7); root = insert(root, 6); root = insert(root, 8); evenNode(root); } } // This code has been contributed // by PrinciRaj1992 |
Output:
2 4 6 8
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