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Iterative Postorder Traversal of N-ary Tree
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Preorder Traversal of an N-ary Tree

Last Updated : 22 Feb, 2023
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Given an N-ary Tree. The task is to write a program to perform the preorder traversal of the given n-ary tree.

Examples:  

Input: 3-Array Tree                      1                  / | \                 /  |   \               2    3     4              / \       / | \             5    6    7  8  9            /   / | \            10  11 12 13  Output: 1 2 5 10 6 11 12 13 3 4 7 8 9  Input:  3-Array Tree                    1                  / | \                 /  |   \               2    3     4              / \       / | \             5    6    7  8  9  Output: 1 2 5 6 3 4 7 8 9

The preorder Traversal of an N-ary Tree is similar to the preorder traversal of a Binary Search Tree or Binary Tree with the only difference that is, all the child nodes of a parent are traversed from left to right in a sequence.
Iterative Preorder Traversal of Binary Tree.

Cases to handle during traversal: Two Cases have been taken care of in this Iterative Preorder Traversal Algorithm: 

  1. Pop the top node from the stack - Top from the stack and insert it into the visited list of nodes.
  2. Push all of the child nodes of Top into the stack from right to left as the traversal from the stack will be carried out in reverse order. As a result, correct preorder traversal is achieved.

Note: In the below python implementation, a "dequeue" is used to implement the stack instead of a list because of its efficient append and pop operations.

Below is the implementation of the above approach:  

C++
// C++ program for Iterative Preorder // Traversal of N-ary Tree. // Preorder{ Root, print children // from left to right. #include <bits/stdc++.h> using namespace std;  // Node Structure of K-ary Tree class NewNode { public:     int key;      // All children are stored in a list     vector<NewNode*> child;     NewNode(int val)         : key(val)     {     } };  // Utility function to print the // preorder of the given K-Ary Tree void preorderTraversal(NewNode* root) {     stack<NewNode*> Stack;      // 'Preorder'-> contains all the     // visited nodes     vector<int> Preorder;      Stack.push(root);      while (!Stack.empty()) {         NewNode* temp = Stack.top();         Stack.pop();         // store the key in preorder vector(visited list)         Preorder.push_back(temp->key);         // Push all of the child nodes of temp into         // the stack from right to left.         for (int i = temp->child.size() - 1; i >= 0; i--) {             Stack.push(temp->child[i]);         }     }     for (auto i : Preorder) {         cout << i << " ";     }     cout << endl; }  // Driver Code int main() {      // input nodes     /*              1           /  |  \          /   |   \         2    3    4        / \      / | \       /   \    7  8  9      5     6     /    / | \    10   11 12 13     */      NewNode* root = new NewNode(1);     root->child.push_back(new NewNode(2));     root->child.push_back(new NewNode(3));     root->child.push_back(new NewNode(4));      root->child[0]->child.push_back(new NewNode(5));     root->child[0]->child[0]->child.push_back(         new NewNode(10));     root->child[0]->child.push_back(new NewNode(6));     root->child[0]->child[1]->child.push_back(         new NewNode(11));     root->child[0]->child[1]->child.push_back(         new NewNode(12));     root->child[0]->child[1]->child.push_back(         new NewNode(13));     root->child[2]->child.push_back(new NewNode(7));     root->child[2]->child.push_back(new NewNode(8));     root->child[2]->child.push_back(new NewNode(9));      preorderTraversal(root); }  // This code is contributed by sarangiswastika5 
Java
// Java program for Iterative Preorder // Traversal of N-ary Tree. // Preorder{ Root, print children // from left to right. import java.util.*;  public class gfg2 {     // Node Structure of K-ary Tree     static class Node {         int key;          // All children are stored in a list         ArrayList<Node> child;          Node(int val)         {             key = val;             child = new ArrayList<>();         }     };      // Utility function to print the     // preorder of the given K-Ary Tree     static void preorderTraversal(Node root)     {         Stack<Node> stack = new Stack<>();          // 'Preorder'-> contains all the         // visited nodes         ArrayList<Integer> Preorder = new ArrayList<>();          stack.push(root);          while (!stack.isEmpty()) {             Node temp = stack.peek();             stack.pop();             // store the key in preorder vector(visited             // list)             Preorder.add(temp.key);             // Push all of the child nodes of temp into             // the stack from right to left.             for (int i = temp.child.size() - 1; i >= 0;                  i--) {                 stack.push(temp.child.get(i));             }         }         for (Integer i : Preorder) {             System.out.print(i + " ");         }         System.out.println();     }      // Driver Code     public static void main(String[] args)     {         // input nodes         /*                 1               /  |  \             /   |   \             2    3    4           / \      / | \           /   \    7  8  9         5     6         /    / | \       10   11 12 13         */          Node root = new Node(1);         root.child.add(new Node(2));         root.child.add(new Node(3));         root.child.add(new Node(4));          root.child.get(0).child.add(new Node(5));         root.child.get(0).child.get(0).child.add(             new Node(10));         root.child.get(0).child.add(new Node(6));         root.child.get(0).child.get(1).child.add(             new Node(11));         root.child.get(0).child.get(1).child.add(             new Node(12));         root.child.get(0).child.get(1).child.add(             new Node(13));         root.child.get(2).child.add(new Node(7));         root.child.get(2).child.add(new Node(8));         root.child.get(2).child.add(new Node(9));          preorderTraversal(root);     } } // This code is contributed by karandeep1234 
Python3
# Python3 program for Iterative Preorder # Traversal of N-ary Tree. # Preorder: Root, print children # from left to right.  from collections import deque  # Node Structure of K-ary Tree   class NewNode():      def __init__(self, val):         self.key = val         # all children are stored in a list         self.child = []   # Utility function to print the # preorder of the given K-Ary Tree def preorderTraversal(root):      Stack = deque([])     # 'Preorder'-> contains all the     # visited nodes.     Preorder = []     Preorder.append(root.key)     Stack.append(root)     while len(Stack) > 0:         # 'Flag' checks whether all the child         # nodes have been visited.         flag = 0         # CASE 1- If Top of the stack is a leaf         # node then remove it from the stack:         if len((Stack[len(Stack)-1]).child) == 0:             X = Stack.pop()             # CASE 2- If Top of the stack is             # Parent with children:         else:             Par = Stack[len(Stack)-1]         # a)As soon as an unvisited child is         # found(left to right sequence),         # Push it to Stack and Store it in         # Auxiliary List(Marked Visited)         # Start Again from Case-1, to explore         # this newly visited child         for i in range(0, len(Par.child)):             if Par.child[i].key not in Preorder:                 flag = 1                 Stack.append(Par.child[i])                 Preorder.append(Par.child[i].key)                 break                 # b)If all Child nodes from left to right                 # of a Parent have been visited                 # then remove the parent from the stack.         if flag == 0:             Stack.pop()     print(Preorder)   # Execution Start From here if __name__ == '__main__':     # input nodes     '''        1    /  |  \   /   |   \  2    3    4 / \      / | \ /   \    7  8  9 5     6     /    / | \  10   11 12 13      '''  root = NewNode(1) root.child.append(NewNode(2)) root.child.append(NewNode(3)) root.child.append(NewNode(4)) root.child[0].child.append(NewNode(5)) root.child[0].child[0].child.append(NewNode(10)) root.child[0].child.append(NewNode(6)) root.child[0].child[1].child.append(NewNode(11)) root.child[0].child[1].child.append(NewNode(12)) root.child[0].child[1].child.append(NewNode(13)) root.child[2].child.append(NewNode(7)) root.child[2].child.append(NewNode(8)) root.child[2].child.append(NewNode(9))  preorderTraversal(root) 
C#
// C# program for Iterative Preorder // Traversal of N-ary Tree. // Preorder{ Root, print children // from left to right. using System; using System.Collections; using System.Collections.Generic;  class gfg2 {      // Node Structure of K-ary Tree     public class Node {         public int key;          // All children are stored in a list         public List<Node> child;          public Node(int val)         {             key = val;             child = new List<Node>();         }     };      // Utility function to print the     // preorder of the given K-Ary Tree     static void preorderTraversal(Node root)     {         Stack<Node> stack = new Stack<Node>();          // 'Preorder'-> contains all the         // visited nodes         List<int> Preorder = new List<int>();          stack.Push(root);          while (stack.Count != 0) {             Node temp = stack.Peek();             stack.Pop();              // store the key in preorder vector(visited             // list)             Preorder.Add(temp.key);              // Push all of the child nodes of temp into             // the stack from right to left.             for (int i = temp.child.Count - 1; i >= 0;                  i--) {                 stack.Push(temp.child[i]);             }         }         foreach(int i in Preorder)         {             Console.Write(i + " ");         }         Console.WriteLine();     }      // Driver Code     public static void Main(string[] args)     {         // input nodes         /*                     1                   /  |  \                 /   |   \                 2    3    4               / \      / | \               /   \    7  8  9             5     6             /    / | \           10   11 12 13             */          Node root = new Node(1);         root.child.Add(new Node(2));         root.child.Add(new Node(3));         root.child.Add(new Node(4));          root.child[0].child.Add(new Node(5));         root.child[0].child[0].child.Add(new Node(10));         root.child[0].child.Add(new Node(6));         root.child[0].child[1].child.Add(new Node(11));         root.child[0].child[1].child.Add(new Node(12));         root.child[0].child[1].child.Add(new Node(13));         root.child[2].child.Add(new Node(7));         root.child[2].child.Add(new Node(8));         root.child[2].child.Add(new Node(9));          preorderTraversal(root);     } }  // This code is contributed by karandeep1234 
JavaScript
// Node Structure of K-ary Tree class NewNode { constructor(val) { this.key = val; // all children are stored in an array this.child = []; } }  // Utility function to print the // preorder of the given K-Ary Tree function preorderTraversal(root) { let stack = []; // 'Preorder'-> contains all the // visited nodes. let preorder = []; preorder.push(root.key); stack.push(root); while (stack.length > 0) { // 'flag' checks whether all the child // nodes have been visited. let flag = 0; // CASE 1- If Top of the stack is a leaf // node then remove it from the stack: if (stack[stack.length - 1].child.length === 0) { let x = stack.pop(); // CASE 2- If Top of the stack is // Parent with children: } else { let par = stack[stack.length - 1]; // a)As soon as an unvisited child is // found(left to right sequence), // Push it to Stack and Store it in // Auxiliary List(Marked Visited) // Start Again from Case-1, to explore // this newly visited child for (let i = 0; i < par.child.length; i++) { if (!preorder.includes(par.child[i].key)) { flag = 1; stack.push(par.child[i]); preorder.push(par.child[i].key); break; } // b)If all Child nodes from left to right // of a Parent have been visited // then remove the parent from the stack. } if (flag === 0) { stack.pop(); } } } document.write(preorder); }  // Execution Start From here  // input nodes /* 1 / | / | 2 3 4 / \ / | / \ 7 8 9 5 6 / / | \ 10 11 12 13 */ let root = new NewNode(1); root.child.push(new NewNode(2)); root.child.push(new NewNode(3)); root.child.push(new NewNode(4)); root.child[0].child.push(new NewNode(5)); root.child[0].child[0].child.push(new NewNode(10)); root.child[0].child.push(new NewNode(6)); root.child[0].child[1].child.push(new NewNode(11)); root.child[0].child[1].child.push(new NewNode(12)); root.child[0].child[1].child.push(new NewNode(13)); root.child[2].child.push(new NewNode(7)) root.child[2].child.push(new NewNode(8)) root.child[2].child.push(new NewNode(9))      preorderTraversal(root) 

Output
1 2 5 10 6 11 12 13 3 4 7 8 9 

Complexity Analysis:

  • Time Complexity: O(N), Where n is the total number of nodes in the given tree.
  • Auxiliary Space: O(h), Where h is the height of the given tree

Using Recursion:

Approach:

  • Create a vector that is used to store the preorder traversal of the N-ary tree.
  • While visiting the node store the value of the node in the vector created and call the recursive function for its children.

Below is the implementation of the above algorithm:

C++
// C++ program for Recursive Preorder Traversal of N-ary // Tree. #include <bits/stdc++.h> using namespace std;  // Node Structure of K-ary Tree struct Node {     char val;     vector<Node*> children; };  // Utility function to create a new tree node Node* newNode(int key) {     Node* temp = new Node;     temp->val = key;     return temp; }  // Recursive function to print the // preorder of the given K-Ary Tree void fun(Node* root, vector<int>& v) {     if (root == NULL) {         return;     }     v.push_back(root->val);     for (int i = 0; i < root->children.size(); i++) {         fun(root->children[i], v);     }     return; }  // Function to print preorder list void preorderTraversal(Node* root) {     vector<int> v;     fun(root, v);     for (auto it : v)         cout << it << " "; }  // Driver Code int main() {      // input nodes     /*               1             / | \            /  |  \           2   3   4          / \     / | \         5   6    7 8  9        /  / | \       10 11 12 13       */      Node* root = newNode(1);     root->children.push_back(newNode(2));     root->children.push_back(newNode(3));     root->children.push_back(newNode(4));      root->children[0]->children.push_back(newNode(5));     root->children[0]->children[0]->children.push_back(         newNode(10));     root->children[0]->children.push_back(newNode(6));     root->children[0]->children[1]->children.push_back(         newNode(11));     root->children[0]->children[1]->children.push_back(         newNode(12));     root->children[0]->children[1]->children.push_back(         newNode(13));     root->children[2]->children.push_back(newNode(7));     root->children[2]->children.push_back(newNode(8));     root->children[2]->children.push_back(newNode(9));      preorderTraversal(root); }  // This code is contributed by Aditya Kumar (adityakumar129) 
Python3
# Python3 program for Recursive Preorder Traversal of N-ary Tree  # Node Structure of K-ary Tree class Node:     def __init__(self, val):         self.val = val         self.children = []  # Utility function to create a new tree node def newNode(key):     temp = Node(key)     return temp  # Recursive function to print the preorder of the given K-Ary Tree def fun(root, v):     if root is None:         return     v.append(root.val)     for i in range(len(root.children)):         fun(root.children[i], v)     return  # Function to print preorder list def preorderTraversal(root):     v = []     fun(root, v)     for it in v:         print(it, end=" ")  # Input nodes '''               1             / | \            /  |  \           2   3   4          / \     / | \         5   6    7 8  9        /  / | \       10 11 12 13 '''  root = newNode(1) root.children.append(newNode(2)) root.children.append(newNode(3)) root.children.append(newNode(4))  root.children[0].children.append(newNode(5)) root.children[0].children[0].children.append(newNode(10)) root.children[0].children.append(newNode(6)) root.children[0].children[1].children.append(newNode(11)) root.children[0].children[1].children.append(newNode(12)) root.children[0].children[1].children.append(newNode(13)) root.children[2].children.append(newNode(7)) root.children[2].children.append(newNode(8)) root.children[2].children.append(newNode(9))  preorderTraversal(root)  # This code is contributed by lokeshpotta20. 
C#
using System; using System.Collections; using System.Collections.Generic;  public class Gfg {   // Node Structure of K-ary Tree   public class Node {     public int val;     public List<Node> children;     public Node(int val)     {       this.val=val;       this.children=new List<Node>();     }   };    // Utility function to create a new tree node   /*Node* newNode(int key)     {         Node* temp = new Node;         temp.val = key;         return temp;     }*/    // Recursive function to print the   // preorder of the given K-Ary Tree   static void fun(Node root, List<int> v)   {     if (root == null) {       return;     }     v.Add(root.val);     for (int i = 0; i < root.children.Count; i++) {       fun(root.children[i], v);     }     return;   }    // Function to print preorder list   static void preorderTraversal(Node root)   {     List<int> v=new List<int>();     fun(root, v);     foreach (int i in v)       Console.Write(i + " ");   }    // Driver Code   public static void Main(string[] args)   {      // input nodes     /*                   1                 / | \                /  |  \               2   3   4              / \     / | \             5   6    7 8  9            /  / | \           10 11 12 13           */      Node root = new Node(1);     root.children.Add(new Node(2));     root.children.Add(new Node(3));     root.children.Add(new Node(4));      root.children[0].children.Add(new Node(5));     root.children[0].children[0].children.Add(       new Node(10));     root.children[0].children.Add(new Node(6));     root.children[0].children[1].children.Add(       new Node(11));     root.children[0].children[1].children.Add(       new Node(12));     root.children[0].children[1].children.Add(       new Node(13));     root.children[2].children.Add(new Node(7));     root.children[2].children.Add(new Node(8));     root.children[2].children.Add(new Node(9));      preorderTraversal(root);   } }  // This code is contributed by poojaagarwal2. 
JavaScript
// Javascript program for Recursive Preorder Traversal of N-ary // Tree.  // Node Structure of K-ary Tree class Node {     /*char val;     vector<Node*> children;*/     constructor(val)     {         this.val=val;         this.children=new Array();     } }  // Utility function to create a new tree node /*Node* newNode(int key) {     Node* temp = new Node;     temp.val = key;     return temp; }*/  // Recursive function to print the // preorder of the given K-Ary Tree function fun( root, v) {     if (root == null) {         return;     }     v.push(root.val);     for (let i = 0; i < root.children.length; i++) {         fun(root.children[i], v);     }     return; }  // Function to print preorder list function preorderTraversal( root) {     v=new Array();     fun(root, v);     for (let it of v)         console.log(it + " "); }  // Driver Code // input nodes /*           1         / | \        /  |  \       2   3   4      / \     / | \     5   6    7 8  9    /  / | \   10 11 12 13   */  let root = new Node(1); root.children.push(new Node(2)); root.children.push(new Node(3)); root.children.push(new Node(4));  root.children[0].children.push(new Node(5)); root.children[0].children[0].children.push(     new Node(10)); root.children[0].children.push(new Node(6)); root.children[0].children[1].children.push(     new Node(11)); root.children[0].children[1].children.push(     new Node(12)); root.children[0].children[1].children.push(     new Node(13)); root.children[2].children.push(new Node(7)); root.children[2].children.push(new Node(8)); root.children[2].children.push(new Node(9));  preorderTraversal(root);  // This code is contributed by ratiagrawal. 
Java
// Java program for Recursive Preorder Traversal of N-ary // Tree.  import java.io.*; import java.util.*;  // Node Structure of K-ary Tree class Node {     int val;     List<Node> children;     Node(int val)     {         this.val = val;         this.children = new ArrayList<>();     } }  class GFG {      // Recursive function to print the preorder of the given     // K-Ary Tree     static void fun(Node root, List<Integer> v)     {         if (root == null) {             return;         }         v.add(root.val);         for (int i = 0; i < root.children.size(); i++) {             fun(root.children.get(i), v);         }     }      // Function to print preorder list     static void preorderTraversal(Node root)     {         List<Integer> v = new ArrayList<>();         fun(root, v);         for (int i : v)             System.out.print(i + " ");     }      public static void main(String[] args)     {         // input nodes         /*                      1                     / | \                    /  |  \                   2   3   4                  / \ /|\                 5  6 7 8 9                / / | \               10 11 12 13         */         Node root = new Node(1);         root.children.add(new Node(2));         root.children.add(new Node(3));         root.children.add(new Node(4));          root.children.get(0).children.add(new Node(5));         root.children.get(0).children.get(0).children.add(             new Node(10));         root.children.get(0).children.add(new Node(6));         root.children.get(0).children.get(1).children.add(             new Node(11));         root.children.get(0).children.get(1).children.add(             new Node(12));         root.children.get(0).children.get(1).children.add(             new Node(13));         root.children.get(2).children.add(new Node(7));         root.children.get(2).children.add(new Node(8));         root.children.get(2).children.add(new Node(9));          preorderTraversal(root);     } }  // This code is contributed by karthik 

Output
1 2 5 10 6 11 12 13 3 4 7 8 9 

Complexity Analysis:

Time Complexity: O(N), Where n is the total number of nodes in the given tree.
Auxiliary Space: O(h), Where h is the height of the given tree if you consider the Auxiliary stack space of the recursion.


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Iterative Postorder Traversal of N-ary Tree

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  • Advanced Data Structure
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    Sum of all elements of N-ary Tree
    Given an n-ary tree consisting of n nodes, the task is to find the sum of all the elements in the given n-ary tree.Example:Input:Output: 268Explanation: The sum of all the nodes is 11 + 21 + 29 + 90 + 18 + 10 + 12 + 77 = 268Input:Output: 360Explanation: The sum of all the nodes is 81 + 26 + 23 + 49
    5 min read
    Serialize and Deserialize an N-ary Tree
    Given an N-ary tree where every node has the most N children. How to serialize and deserialize it? Serialization is to store a tree in a file so that it can be later restored. The structure of the tree must be maintained. Deserialization is reading the tree back from the file. This post is mainly an
    11 min read

    Easy problems on n-ary Tree

    Check if the given n-ary tree is a binary tree
    Given an n-ary tree consisting of n nodes, the task is to check whether the given tree is binary or not.Note: An n-ary tree is a tree where each node can have zero or more children nodes. Unlike a binary tree, which has at most two children per node (left and right), the n-ary tree allows for multip
    6 min read
    Largest element in an N-ary Tree
    Given an n-ary tree containing positive node values, the task is to find the node with the largest value in the given n-ary tree.Note: An n-ary tree is a tree where each node can have zero or more children nodes. Unlike a binary tree, which has at most two children per node (left and right), the n-a
    5 min read
    Second Largest element in n-ary tree
    Given an n-ary tree containing positive node values, the task is to find the node with the second largest value in the given n-ary tree. If there is no second largest node return -1.Note: An n-ary tree is a tree where each node can have zero or more children nodes. Unlike a binary tree, which has at
    7 min read
    Number of children of given node in n-ary Tree
    Given a node x, find the number of children of x(if it exists) in the given n-ary tree. Example : Input : x = 50 Output : 3 Explanation : 50 has 3 children having values 40, 100 and 20. Approach : Initialize the number of children as 0.For every node in the n-ary tree, check if its value is equal to
    7 min read
    Number of nodes greater than a given value in n-ary tree
    Given a n-ary tree and a number x, find and return the number of nodes which are greater than x. Example: In the given tree, x = 7 Number of nodes greater than x are 4. Approach: The idea is maintain a count variable initialize to 0. Traverse the tree and compare root data with x. If root data is gr
    6 min read
    Check mirror in n-ary tree
    Given two n-ary trees, determine whether they are mirror images of each other. Each tree is described by e edges, where e denotes the number of edges in both trees. Two arrays A[]and B[] are provided, where each array contains 2*e space-separated values representing the edges of both trees. Each edg
    11 min read
    Replace every node with depth in N-ary Generic Tree
    Given an array arr[] representing a Generic(N-ary) tree. The task is to replace the node data with the depth(level) of the node. Assume level of root to be 0. Array Representation: The N-ary tree is serialized in the array arr[] using level order traversal as described below:   The input is given as
    15+ min read
    Preorder Traversal of N-ary Tree Without Recursion
    Given an n-ary tree containing positive node values. The task is to print the preorder traversal without using recursion.Note: An n-ary tree is a tree where each node can have zero or more children. Unlike a binary tree, which has at most two children per node (left and right), the n-ary tree allows
    6 min read
    Maximum value at each level in an N-ary Tree
    Given a N-ary Tree consisting of nodes valued in the range [0, N - 1] and an array arr[] where each node i is associated to value arr[i], the task is to print the maximum value associated with any node at each level of the given N-ary Tree. Examples: Input: N = 8, Edges[][] = {{0, 1}, {0, 2}, {0, 3}
    9 min read
    Replace each node in given N-ary Tree with sum of all its subtrees
    Given an N-ary tree. The task is to replace the values of each node with the sum of all its subtrees and the node itself. Examples Input: 1 / | \ 2 3 4 / \ \ 5 6 7Output: Initial Pre-order Traversal: 1 2 5 6 7 3 4 Final Pre-order Traversal: 28 20 5 6 7 3 4 Explanation: Value of each node is replaced
    8 min read
    Path from the root node to a given node in an N-ary Tree
    Given an integer N and an N-ary Tree of the following form: Every node is numbered sequentially, starting from 1, till the last level, which contains the node N.The nodes at every odd level contains 2 children and nodes at every even level contains 4 children. The task is to print the path from the
    10 min read
    Determine the count of Leaf nodes in an N-ary tree
    Given the value of 'N' and 'I'. Here, I represents the number of internal nodes present in an N-ary tree and every node of the N-ary can either have N childs or zero child. The task is to determine the number of Leaf nodes in n-ary tree. Examples: Input : N = 3, I = 5 Output : Leaf nodes = 11 Input
    4 min read
    Remove all leaf nodes from a Generic Tree or N-ary Tree
    Given an n-ary tree containing positive node values, the task is to delete all the leaf nodes from the tree and print preorder traversal of the tree after performing the deletion.Note: An n-ary tree is a tree where each node can have zero or more children nodes. Unlike a binary tree, which has at mo
    6 min read
    Maximum level sum in N-ary Tree
    Given an N-ary Tree consisting of nodes valued [1, N] and an array value[], where each node i is associated with value[i], the task is to find the maximum of sum of all node values of all levels of the N-ary Tree. Examples: Input: N = 8, Edges[][2] = {{0, 1}, {0, 2}, {0, 3}, {1, 4}, {1, 5}, {3, 6},
    9 min read
    Number of leaf nodes in a perfect N-ary tree of height K
    Find the number of leaf nodes in a perfect N-ary tree of height K. Note: As the answer can be very large, return the answer modulo 109+7. Examples: Input: N = 2, K = 2Output: 4Explanation: A perfect Binary tree of height 2 has 4 leaf nodes. Input: N = 2, K = 1Output: 2Explanation: A perfect Binary t
    4 min read
    Print all root to leaf paths of an N-ary tree
    Given an N-Ary tree, the task is to print all root to leaf paths of the given N-ary Tree. Examples: Input: 1 / \ 2 3 / / \ 4 5 6 / \ 7 8 Output:1 2 41 3 51 3 6 71 3 6 8 Input: 1 / | \ 2 5 3 / \ \ 4 5 6Output:1 2 41 2 51 51 3 6 Approach: The idea to solve this problem is to start traversing the N-ary
    7 min read
    Minimum distance between two given nodes in an N-ary tree
    Given a N ary Tree consisting of N nodes, the task is to find the minimum distance from node A to node B of the tree. Examples: Input: 1 / \ 2 3 / \ / \ \4 5 6 7 8A = 4, B = 3Output: 3Explanation: The path 4->2->1->3 gives the minimum distance from A to B. Input: 1 / \ 2 3 / \ \ 6 7 8A = 6,
    11 min read
    Average width in a N-ary tree
    Given a Generic Tree consisting of N nodes, the task is to find the average width for each node present in the given tree. The average width for each node can be calculated by the ratio of the total number of nodes in that subtree(including the node itself) to the total number of levels under that n
    8 min read
    Maximum width of an N-ary tree
    Given an N-ary tree, the task is to find the maximum width of the given tree. The maximum width of a tree is the maximum of width among all levels. Examples: Input: 4 / | \ 2 3 -5 / \ /\ -1 3 -2 6 Output: 4 Explanation: Width of 0th level is 1. Width of 1st level is 3. Width of 2nd level is 4. There
    9 min read
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