# Inorder traversal of an N-ary Tree

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 5 3 1 4 6

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

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:

## C++

 `// C++ implementation of the approach ` `#include ` `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 = (Node**)``malloc``(``sizeof``(Node*)*n); ` `        ``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 = ``new` `Node(n, 2); ` `    ``root->children = ``new` `Node(n, 3); ` `    ``root->children = ``new` `Node(n, 4); ` `    ``root->children->children = ``new` `Node(n, 5); ` `    ``root->children->children = ``new` `Node(n, 6); ` `    ``root->children->children = ``new` `Node(n, 7); ` ` `  `    ``inorder(root); ` `    ``return` `0; ` `} ` ` `  `// This code is Contributed by Arnab Kundu `

## 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 = ``new` `Node(n, 2);  ` `        ``root.children = ``new` `Node(n, 3);  ` `        ``root.children = ``new` `Node(n, 4);  ` `        ``root.children.children = ``new` `Node(n, 5);  ` `        ``root.children.children = ``new` `Node(n, 6);  ` `        ``root.children.children = ``new` `Node(n, 7);  ` ` `  `        ``inorder(root);  ` `    ``}  ` `}  ` ` `  `// This code is contributed by AnkitRai01 `

Output:

```5 6 2 7 3 1 4
```

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