Given an N-ary tree containing, the task is to print the inorder traversal of the tree.
Examples:
Input: N = 3
Output: 5 6 2 7 3 1 4
Input: N = 3
Output: 2 3 5 1 4 6
Approach: The inorder traversal of an N-ary tree is defined as visiting all the children except the last then the root and finally the last child recursively.
- Recursively visit the first child.
- Recursively visit the second child.
- .....
- Recursively visit the second last child.
- Print the data in the node.
- Recursively visit the last child.
- Repeat the above steps till all the nodes are visited.
Below is the implementation of the above approach:
Java
// Java implementation of the approach
class GFG {
// Class for the node of the tree
static class Node {
int data;
// List of children
Node children[];
Node(int n, int data)
{
children = new Node[n];
this.data = data;
}
}
// Function to print the inorder traversal
// of the n-ary tree
static void inorder(Node node)
{
if (node == null)
return;
// Total children count
int total = node.children.length;
// All the children except the last
for (int i = 0; i < total - 1; i++)
inorder(node.children[i]);
// Print the current node's data
System.out.print("" + node.data + " ");
// Last child
inorder(node.children[total - 1]);
}
// Driver code
public static void main(String[] args)
{
/* Create the following tree
1
/ | \
2 3 4
/ | \
5 6 7
*/
int n = 3;
Node root = new Node(n, 1);
root.children[0] = new Node(n, 2);
root.children[1] = new Node(n, 3);
root.children[2] = new Node(n, 4);
root.children[0].children[0] = new Node(n, 5);
root.children[0].children[1] = new Node(n, 6);
root.children[0].children[2] = new Node(n, 7);
inorder(root);
}
}
Python3
# Python3 implementation of the approach
class GFG:
# Class for the node of the tree
class Node:
def __init__(self,n,data):
# List of children
self.children = [None]*n
self.data = data
# Function to print the inorder traversal
# of the n-ary tree
def inorder(self, node):
if node == None:
return
# Total children count
total = len(node.children)
# All the children except the last
for i in range(total-1):
self.inorder(node.children[i])
# Print the current node's data
print(node.data,end=" ")
# Last child
self.inorder(node.children[total-1])
# Driver code
def main(self):
# Create the following tree
# 1
# / | \
# 2 3 4
# / | \
# 5 6 7
n = 3
root = self.Node(n, 1)
root.children[0] = self.Node(n, 2)
root.children[1] = self.Node(n, 3)
root.children[2] = self.Node(n, 4)
root.children[0].children[0] = self.Node(n, 5)
root.children[0].children[1] = self.Node(n, 6)
root.children[0].children[2] = self.Node(n, 7)
self.inorder(root)
ob = GFG() # Create class object
ob.main() # Call main function
# This code is contributed by Shivam Singh
C#
// C# implementation of the approach
using System;
class GFG
{
// Class for the node of the tree
public class Node
{
public int data;
// List of children
public Node []children;
public Node(int n, int data)
{
children = new Node[n];
this.data = data;
}
}
// Function to print the inorder traversal
// of the n-ary tree
static void inorder(Node node)
{
if (node == null)
return;
// Total children count
int total = node.children.Length;
// All the children except the last
for (int i = 0; i < total - 1; i++)
inorder(node.children[i]);
// Print the current node's data
Console.Write("" + node.data + " ");
// Last child
inorder(node.children[total - 1]);
}
// Driver code
public static void Main()
{
/* Create the following tree
1
/ | \
2 3 4
/ | \
5 6 7
*/
int n = 3;
Node root = new Node(n, 1);
root.children[0] = new Node(n, 2);
root.children[1] = new Node(n, 3);
root.children[2] = new Node(n, 4);
root.children[0].children[0] = new Node(n, 5);
root.children[0].children[1] = new Node(n, 6);
root.children[0].children[2] = new Node(n, 7);
inorder(root);
}
}
// This code is contributed by AnkitRai01
Javascript
<script>
// JavaScript implementation of the approach
// Class for the node of the tree
class Node
{
constructor(n, data)
{
this.data = data;
this.children = Array(n);
}
}
// Function to print the inorder traversal
// of the n-ary tree
function inorder(node)
{
if (node == null)
return;
// Total children count
var total = node.children.length;
// All the children except the last
for (var i = 0; i < total - 1; i++)
inorder(node.children[i]);
// Print the current node's data
document.write("" + node.data + " ");
// Last child
inorder(node.children[total - 1]);
}
// Driver code
/* Create the following tree
1
/ | \
2 3 4
/ | \
5 6 7
*/
var n = 3;
var root = new Node(n, 1);
root.children[0] = new Node(n, 2);
root.children[1] = new Node(n, 3);
root.children[2] = new Node(n, 4);
root.children[0].children[0] = new Node(n, 5);
root.children[0].children[1] = new Node(n, 6);
root.children[0].children[2] = new Node(n, 7);
inorder(root);
</script>
C++
// C++ implementation of the approach
#include<bits/stdc++.h>
using namespace std;
// Class for the node of the tree
struct Node
{
int data;
// List of children
struct Node **children;
int length;
Node()
{
length = 0;
data = 0;
}
Node(int n, int data_)
{
children = new Node*();
length = n;
data = data_;
}
};
// Function to print the inorder traversal
// of the n-ary tree
void inorder(Node *node)
{
if (node == NULL)
return;
// Total children count
int total = node->length;
// All the children except the last
for (int i = 0; i < total - 1; i++)
inorder(node->children[i]);
// Print the current node's data
cout<< node->data << " ";
// Last child
inorder(node->children[total - 1]);
}
// Driver code
int main()
{
/* Create the following tree
1
/ | \
2 3 4
/ | \
5 6 7
*/
int n = 3;
Node* root = new Node(n, 1);
root->children[0] = new Node(n, 2);
root->children[1] = new Node(n, 3);
root->children[2] = new Node(n, 4);
root->children[0]->children[0] = new Node(n, 5);
root->children[0]->children[1] = new Node(n, 6);
root->children[0]->children[2] = new Node(n, 7);
inorder(root);
return 0;
}
// This code is Contributed by Arnab Kundu
Output
5 6 2 7 3 1 4
Time Complexity: O(n)
Space Complexity: O(n)