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Find shortest unique prefix for every word in a given list

Here given code implementation process.

/*
  Java program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
    // Indicates end of string
    public boolean last;
    public TreeNode[] children;
    public int count;
    public TreeNode()
    {
        this.last = false;
        this.children = new TreeNode[26];
        this.count = 1;
    }
}
public class Trie
{
    public TreeNode root;
    public Trie()
    {
        this.root = new TreeNode();
    }
    public void insert(String text)
    {
        // First get the length of text
        int length = text.length();
        // This variable are used to task find the index location of character
        int index = 0;
        // Get the root node
        TreeNode head = this.root;
        for (int level = 0; level < length; level++)
        {
            // Get the index
            index = text.charAt(level) - 'a';
            if (head.children[index] == null)
            {
                // When need to add new Node
                head.children[index] = new TreeNode();
            }
            else
            {
                head.children[index].count++;
            }
            head = head.children[index];
        }
        if (head != null)
        {
            // indicates end of string
            head.last = true;
        }
    }
    public void shortestPrefix(TreeNode head, String output)
    {
        if (head != null)
        {
            for (int i = 0; i < 26; ++i)
            {
                if (head.children[i] != null)
                {
                    if (head.children[i].count == 1)
                    {
                        // Display Result
                        System.out.println(output + ((char)(i + 97)));
                    }
                    else
                    {
                        // Find short prefix
                        shortestPrefix(head.children[i], output + ((char)(i + 97)));
                    }
                }
            }
        }
    }
    public static void main(String[] args)
    {
        // Make Tree
        Trie task = new Trie();
        // Add word
        task.insert("bring");
        task.insert("workout");
        task.insert("break");
        task.insert("word");
        task.insert("works");
        task.insert("wordlike");
        task.insert("bress");


        // Test
        // ----
        // ➀ ["bring","break","bress"] this start with "br"
        //   Scan "br"
        //  "bring"
        //   --
        //      
        //  "break"  
        //   --│    
        //     ↓      
        //  "bress"   unique["bri", "brea","bres"]
        //   --       Note "bre" common in ["break","bress"]
        // ------------------------------------------------------
        //                    -      -      -
        // ➁ ["word","wordlike",workout","works"] this start with "wor"
        //  Scan "wor"
        //  "word" 
        //   ---│
        //      ↓
        //  "wordlike"
        //            Common in both is "word" unique ["wordl"]
        //            Note not taken "word" because after d no character
        //  "workout"
        //   ---│
        //      ↓
        //  "works"
        //        Common in both is "work" unique ["worko","works"]   
        // ------------------------------------------------------
        // Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
        task.shortestPrefix(task.root, "");
    }
}

Output

brea
bres
bri
wordl
worko
works

// Include header file
#include <iostream>
#include <string>
using namespace std;
/*
  C++ program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
	public:
	// Indicates end of string
	bool last;
    TreeNode *children[26];
	int count;
    TreeNode()
    {
        this->last = false;
        for (int i = 0; i < 26; ++i)
        {
            this->children[i] = NULL;
        }
      	this->count = 1;
    }
};
class Trie
{
	public: TreeNode *root;
	Trie()
	{
		this->root = new TreeNode();
	}
	void insert(string text)
	{
		// First get the length of text
		int length = text.length();
		// This variable are used to task find the index location of character
		int index = 0;
		// Get the root node
		TreeNode *head = this->root;
		for (int level = 0; level < length; level++)
		{
			// Get the index
			index = text[level] - 'a';
			if (head->children[index] == NULL)
			{
				// When need to add new Node
				head->children[index] = new TreeNode();
			}
			else
			{
				head->children[index]->count++;
			}
			head = head->children[index];
		}
		if (head != NULL)
		{
			// indicates end of string
			head->last = true;
		}
	}
	void shortestPrefix(TreeNode *head, string output)
	{
		if (head != NULL)
		{
			for (int i = 0; i < 26; ++i)
			{
				if (head->children[i] != NULL)
				{
					if (head->children[i]->count == 1)
					{
						// Display Result
						cout << output + ((char)(i + 97)) << endl;
					}
					else
					{
						// Find short prefix
						this->shortestPrefix(
                          head->children[i], output  +  
                          (((char)(i + 97))));
					}
				}
			}
		}
	}
};
int main()
{
	// Make Tree
	Trie *task = new Trie();
	// Add word
	task->insert("bring");
	task->insert("workout");
	task->insert("break");
	task->insert("word");
	task->insert("works");
	task->insert("wordlike");
	task->insert("bress");
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task->shortestPrefix(task->root, "");
	return 0;
}

Output

brea
bres
bri
wordl
worko
works

package main
import "fmt"
/*
  Go program
  Find shortest unique prefix for every word in a given list
*/
type TreeNode struct {
	// Indicates end of string
	last bool
	children [] *TreeNode 
	count int
}
func getTreeNode() * TreeNode {
	var me *TreeNode = &TreeNode {}
	me.last = false
	me.children = make([] *TreeNode, 26)
	me.count = 1
	return me
}
type Trie struct {
	root * TreeNode
}
func getTrie() * Trie {
	var me *Trie = &Trie {}
	me.root = getTreeNode()
	return me
}
func(this Trie) insert(text string) {
	// First get the length of text
	var length int = len(text)
	// This variable are used to task find the index location of character
	var index int = 0
	// Get the root node
	var head * TreeNode = this.root
	for level := 0 ; level < length ; level++ {
		// Get the index
		index = int(text[level]) - int('a')
		if head.children[index] == nil {
			// When need to add new Node
			head.children[index] = getTreeNode()
		} else {
			head.children[index].count++
		}
		head = head.children[index]
	}
	if head != nil {
		// indicates end of string
		head.last = true
	}
}
func(this Trie) shortestPrefix(head * TreeNode, output string) {
	if head != nil {
		for i := 0 ; i < 26 ; i++ {
			if head.children[i] != nil {
				if head.children[i].count == 1 {
					// Display Result
					fmt.Println(output+string(byte((i + 97))))
				} else {
					// Find short prefix
					this.shortestPrefix(head.children[i], 
						output + string((byte((i + 97)))))
				}
			}
		}
	}
}
func main() {
	// Make Tree
	var task * Trie = getTrie()
	// Add word
	task.insert("bring")
	task.insert("workout")
	task.insert("break")
	task.insert("word")
	task.insert("works")
	task.insert("wordlike")
	task.insert("bress")
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "")
}

Output

brea
bres
bri
wordl
worko
works

// Include namespace system
using System;
/*
  Csharp program
  Find shortest unique prefix for every word in a given list
*/
public class TreeNode
{
	// Indicates end of string
	public Boolean last;
	public TreeNode[] children;
	public int count;
	public TreeNode()
	{
		this.last = false;
		this.children = new TreeNode[26];
		this.count = 1;
	}
}
public class Trie
{
	public TreeNode root;
	public Trie()
	{
		this.root = new TreeNode();
	}
	public void insert(String text)
	{
		// First get the length of text
		int length = text.Length;
		// This variable are used to task find the index location of character
		int index = 0;
		// Get the root node
		TreeNode head = this.root;
		for (int level = 0; level < length; level++)
		{
			// Get the index
			index = text[level] - 'a';
			if (head.children[index] == null)
			{
				// When need to add new Node
				head.children[index] = new TreeNode();
			}
			else
			{
				head.children[index].count++;
			}
			head = head.children[index];
		}
		if (head != null)
		{
			// indicates end of string
			head.last = true;
		}
	}
	public void shortestPrefix(TreeNode head, String output)
	{
		if (head != null)
		{
			for (int i = 0; i < 26; ++i)
			{
				if (head.children[i] != null)
				{
					if (head.children[i].count == 1)
					{
						// Display Result
						Console.WriteLine(output + ((char)(i + 97)));
					}
					else
					{
						// Find short prefix
						this.shortestPrefix(head.children[i], 
                                            output + ((char)(i + 97)));
					}
				}
			}
		}
	}
	public static void Main(String[] args)
	{
		// Make Tree
		Trie task = new Trie();
		// Add word
		task.insert("bring");
		task.insert("workout");
		task.insert("break");
		task.insert("word");
		task.insert("works");
		task.insert("wordlike");
		task.insert("bress");
		// Test
		// ----
		// ➀ ["bring","break","bress"] this start with "br"
		//   Scan "br"
		//  "bring"
		//   --
		//      
		//  "break"  
		//   --│    
		//     ↓      
		//  "bress"   unique["bri", "brea","bres"]
		//   --       Note "bre" common in ["break","bress"]
		// ------------------------------------------------------
		//                    -      -      -
		// ➁ ["word","wordlike",workout","works"] this start with "wor"
		//  Scan "wor"
		//  "word" 
		//   ---│
		//      ↓
		//  "wordlike"
		//            Common in both is "word" unique ["wordl"]
		//            Note not taken "word" because after d no character
		//  "workout"
		//   ---│
		//      ↓
		//  "works"
		//        Common in both is "work" unique ["worko","works"]   
		// ------------------------------------------------------
		// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
		task.shortestPrefix(task.root, "");
	}
}

Output

brea
bres
bri
wordl
worko
works

<?php
/*
  Php program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
	// Indicates end of string
	public $last;
	public $children;
	public $count;
	public	function __construct()
	{
		$this->last = false;
		$this->children = array_fill(0, 26, NULL);
		$this->count = 1;
	}
}
class Trie
{
	public $root;
	public	function __construct()
	{
		$this->root = new TreeNode();
	}
	public	function insert($text)
	{
		// First get the length of text
		$length = strlen($text);
		// This variable are used to task find the index location of character
		$index = 0;
		// Get the root node
		$head = $this->root;
		for ($level = 0; $level < $length; $level++)
		{
			// Get the index
			$index = ord($text[$level]) - ord('a');
			if ($head->children[$index] == NULL)
			{
				// When need to add new Node
				$head->children[$index] = new TreeNode();
			}
			else
			{
				$head->children[$index]->count++;
			}
			$head = $head->children[$index];
		}
		if ($head != NULL)
		{
			// indicates end of string
			$head->last = true;
		}
	}
	public	function shortestPrefix($head, $output)
	{
		if ($head != NULL)
		{
			for ($i = 0; $i < 26; ++$i)
			{
				if ($head->children[$i] != NULL)
				{
					if ($head->children[$i]->count == 1)
					{
						// Display Result
						echo($output.(chr(($i + 97))).
							"\n");
					}
					else
					{
						// Find short prefix
						$this->shortestPrefix($head->children[$i],
                                              $output.strval((chr(($i + 97)))));
					}
				}
			}
		}
	}
}

function main()
{
	// Make Tree
	$task = new Trie();
	// Add word
	$task->insert("bring");
	$task->insert("workout");
	$task->insert("break");
	$task->insert("word");
	$task->insert("works");
	$task->insert("wordlike");
	$task->insert("bress");
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	$task->shortestPrefix($task->root, "");
}
main();

Output

brea
bres
bri
wordl
worko
works

/*
  Node JS program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
	constructor()
	{
		this.last = false;
		this.children = Array(26).fill(null);
		this.count = 1;
	}
}
class Trie
{
	constructor()
	{
		this.root = new TreeNode();
	}
	insert(text)
	{
		// First get the length of text
		var length = text.length;
		// This variable are used to task find the index location of character
		var index = 0;
		// Get the root node
		var head = this.root;
		for (var level = 0; level < length; level++)
		{
			// Get the index
			index = text.charAt(level).charCodeAt(0) - 'a'.charCodeAt(0);
			if (head.children[index] == null)
			{
				// When need to add new Node
				head.children[index] = new TreeNode();
			}
			else
			{
				head.children[index].count++;
			}
			head = head.children[index];
		}
		if (head != null)
		{
			// indicates end of string
			head.last = true;
		}
	}
	shortestPrefix(head, output)
	{
		if (head != null)
		{
			for (var i = 0; i < 26; ++i)
			{
				if (head.children[i] != null)
				{
					if (head.children[i].count == 1)
					{
						// Display Result
						console.log(output + (String.fromCharCode((i + 97))));
					}
					else
					{
						// Find short prefix
						this.shortestPrefix(head.children[i], 
                               output + (String.fromCharCode((i + 97))));
					}
				}
			}
		}
	}
}

function main()
{
	// Make Tree
	var task = new Trie();
	// Add word
	task.insert("bring");
	task.insert("workout");
	task.insert("break");
	task.insert("word");
	task.insert("works");
	task.insert("wordlike");
	task.insert("bress");
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "");
}
main();

Output

brea
bres
bri
wordl
worko
works

#  Python 3 program
#  Find shortest unique prefix for every word in a given list
class TreeNode :
	
	def __init__(self) :
    	#  Indicates end of string
		self.last = False
		self.children = [None] * (26)
		self.count = 1
	

class Trie :
	def __init__(self) :
		self.root = TreeNode()
	
	def insert(self, text) :
		#  First get the length of text
		length = len(text)
		#  This variable are used to task find the index location of character
		index = 0
		#  Get the root node
		head = self.root
		level = 0
		while (level < length) :
			#  Get the index
			index = ord(text[level]) - ord('a')
			if (head.children[index] == None) :
				#  When need to add new Node
				head.children[index] = TreeNode()
			else :
				head.children[index].count += 1
			
			head = head.children[index]
			level += 1
		
		if (head != None) :
			#  indicates end of string
			head.last = True
		
	
	def shortestPrefix(self, head, output) :
		if (head != None) :
			i = 0
			while (i < 26) :
				if (head.children[i] != None) :
					if (head.children[i].count == 1) :
						#  Display Result
						print(output + (chr((i + 97))))
					else :
						#  Find short prefix
						self.shortestPrefix(head.children[i], 
                             output + str((chr((i + 97)))))
					
				
				i += 1
			
		
	

def main() :
	#  Make Tree
	task = Trie()
	#  Add word
	task.insert("bring")
	task.insert("workout")
	task.insert("break")
	task.insert("word")
	task.insert("works")
	task.insert("wordlike")
	task.insert("bress")
	#  Test
	#  ----
	#  ➀ ["bring","break","bress"] this start with "br"
	#    Scan "br"
	#   "bring"
	#    --
	#   "break"  
	#    --│    
	#      ↓      
	#   "bress"   unique["bri", "brea","bres"]
	#    --       Note "bre" common in ["break","bress"]
	#  ------------------------------------------------------
	#                     -      -      -
	#  ➁ ["word","wordlike",workout","works"] this start with "wor"
	#   Scan "wor"
	#   "word" 
	#    ---│
	#       ↓
	#   "wordlike"
	#             Common in both is "word" unique ["wordl"]
	#             Note not taken "word" because after d no character
	#   "workout"
	#    ---│
	#       ↓
	#   "works"
	#         Common in both is "work" unique ["worko","works"]   
	#  ------------------------------------------------------
	#  Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "")

if __name__ == "__main__": main()

Output

brea
bres
bri
wordl
worko
works

#  Ruby program
#  Find shortest unique prefix for every word in a given list
class TreeNode 
	# Define the accessor and reader of class TreeNode
	attr_reader :last, :children, :count
	attr_accessor :last, :children, :count
	#  Indicates end of string
	Array.new() {nil}
	def initialize() 
		self.last = false
		self.children = Array.new(26) {nil}
		self.count = 1
	end

end

class Trie 
	# Define the accessor and reader of class Trie
	attr_reader :root
	attr_accessor :root
	def initialize() 
		self.root = TreeNode.new()
	end

	def insert(text) 
		#  First get the length of text
		length = text.length
		#  This variable are used to task find the index location of character
		index = 0
		#  Get the root node
		head = self.root
		level = 0
		while (level < length) 
			#  Get the index
			index = text[level].ord - 'a'.ord
			if (head.children[index] == nil) 
				#  When need to add new Node
				head.children[index] = TreeNode.new()
			else
				head.children[index].count += 1
			end

			head = head.children[index]
			level += 1
		end

		if (head != nil) 
			#  indicates end of string
			head.last = true
		end

	end

	def shortestPrefix(head, output) 
		if (head != nil) 
			i = 0
			while (i < 26) 
				if (head.children[i] != nil) 
					if (head.children[i].count == 1) 
						#  Display Result
						print(output + (((i + 97)).chr), "\n")
					else
 
						#  Find short prefix
						self.shortestPrefix(head.children[i], 
                                 output +(((i + 97)).chr).to_s)
					end

				end

				i += 1
			end

		end

	end

end

def main() 
	#  Make Tree
	task = Trie.new()
	#  Add word
	task.insert("bring")
	task.insert("workout")
	task.insert("break")
	task.insert("word")
	task.insert("works")
	task.insert("wordlike")
	task.insert("bress")
	#  Test
	#  ----
	#  ➀ ["bring","break","bress"] this start with "br"
	#    Scan "br"
	#   "bring"
	#    --
	#   "break"  
	#    --│    
	#      ↓      
	#   "bress"   unique["bri", "brea","bres"]
	#    --       Note "bre" common in ["break","bress"]
	#  ------------------------------------------------------
	#                     -      -      -
	#  ➁ ["word","wordlike",workout","works"] this start with "wor"
	#   Scan "wor"
	#   "word" 
	#    ---│
	#       ↓
	#   "wordlike"
	#             Common in both is "word" unique ["wordl"]
	#             Note not taken "word" because after d no character
	#   "workout"
	#    ---│
	#       ↓
	#   "works"
	#         Common in both is "work" unique ["worko","works"]   
	#  ------------------------------------------------------
	#  Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "")
end

main()

Output

brea
bres
bri
wordl
worko
works

import scala.collection.mutable._;
/*
  Scala program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode(
	// Indicates end of string
	var last: Boolean,
		var children: Array[TreeNode],
			var count: Int)
{
	def this()
	{
		this(false, Array.fill[TreeNode](26)(null), 1);
	}
}
class Trie(var root: TreeNode)
{
	def this()
	{
		this(new TreeNode());
	}
	def insert(text: String): Unit = {
		// First get the length of text
		var length: Int = text.length();
		// This variable are used to task find the index location of character
		var index: Int = 0;
		// Get the root node
		var head: TreeNode = this.root;
		var level: Int = 0;
		while (level < length)
		{
			// Get the index
			index = text.charAt(level).toInt - 'a'.toInt;
			if (head.children(index) == null)
			{
				// When need to add new Node
				head.children(index) = new TreeNode();
			}
			else
			{
				head.children(index).count += 1;
			}
			head = head.children(index);
			level += 1;
		}
		if (head != null)
		{
			// indicates end of string
			head.last = true;
		}
	}
	def shortestPrefix(head: TreeNode, output: String): Unit = {
		if (head != null)
		{
			var i: Int = 0;
			while (i < 26)
			{
				if (head.children(i) != null)
				{
					if (head.children(i).count == 1)
					{
						// Display Result
						println(output + ((i + 97).toChar));
					}
					else
					{
						// Find short prefix
						shortestPrefix(head.children(i), 
                        output + ((i + 97).toChar).toString());
					}
				}
				i += 1;
			}
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		// Make Tree
		var task: Trie = new Trie();
		// Add word
		task.insert("bring");
		task.insert("workout");
		task.insert("break");
		task.insert("word");
		task.insert("works");
		task.insert("wordlike");
		task.insert("bress");
		// Test
		// ----
		// ➀ ["bring","break","bress"] this start with "br"
		//   Scan "br"
		//  "bring"
		//   --
		//      
		//  "break"  
		//   --│    
		//     ↓      
		//  "bress"   unique["bri", "brea","bres"]
		//   --       Note "bre" common in ["break","bress"]
		// ------------------------------------------------------
		//                    -      -      -
		// ➁ ["word","wordlike",workout","works"] this start with "wor"
		//  Scan "wor"
		//  "word" 
		//   ---│
		//      ↓
		//  "wordlike"
		//            Common in both is "word" unique ["wordl"]
		//            Note not taken "word" because after d no character
		//  "workout"
		//   ---│
		//      ↓
		//  "works"
		//        Common in both is "work" unique ["worko","works"]   
		// ------------------------------------------------------
		// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
		task.shortestPrefix(task.root, "");
	}
}

Output

brea
bres
bri
wordl
worko
works

import Foundation;
/*
  Swift 4 program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
	// Indicates end of string
	var last: Bool;
	var children: [TreeNode?];
	var count: Int;
	init()
	{
		self.last = false;
		self.children = Array(repeating: nil, count: 26);
		self.count = 1;
	}
}
class Trie
{
	var root: TreeNode? ;
	init()
	{
		self.root = TreeNode();
	}
	func insert(_ data: String)
	{
      	let text = Array(data);
		// First get the length of text
		let length: Int = text.count;
		// This variable are used to task find the index location of character
		var index: Int = 0;
		// Get the root node
		var head: TreeNode? = self.root;
		var level: Int = 0;
		while (level < length)
		{
			// Get the index
			index = Int(
              UnicodeScalar(String(text[level]))!.value) - 
              Int(UnicodeScalar(String("a"))!.value
            );
			if (head!.children[index] == nil)
			{
				// When need to add new Node
				head!.children[index] = TreeNode();
			}
			else
			{
				head!.children[index]!.count += 1;
			}
			head = head!.children[index];
			level += 1;
		}
		if (head  != nil)
		{
			// indicates end of string
			head!.last = true;
		}
	}
	func shortestPrefix(_ head: TreeNode? , _ output : String)
	{
		if (head  != nil)
		{
          	let startingValue = Int(("a" as UnicodeScalar).value); //97
			var i: Int = 0;
			while (i < 26)
			{
				if (head!.children[i]  != nil)
				{
					if (head!.children[i]!.count == 1)
					{
						// Display Result
						print(output + String(Character(
                          UnicodeScalar(i + startingValue)!)));
					}
					else
					{
						// Find short prefix
						self.shortestPrefix(head!.children[i], 
                          output + String(Character(
                            UnicodeScalar(i + startingValue)!)));
					}
				}
				i += 1;
			}
		}
	}
}
func main()
{
	// Make Tree
	let task: Trie = Trie();
	// Add word
	task.insert("bring");
	task.insert("workout");
	task.insert("break");
	task.insert("word");
	task.insert("works");
	task.insert("wordlike");
	task.insert("bress");
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "");
}
main();

Output

brea
bres
bri
wordl
worko
works

/*
  Kotlin program
  Find shortest unique prefix for every word in a given list
*/
class TreeNode
{
	// Indicates end of string
	var last: Boolean;
	var children: Array < TreeNode ? > ;
	var count: Int;
	constructor()
	{
		this.last = false;
		this.children = Array(26)
		{
			null
		};
		this.count = 1;
	}
}
class Trie
{
	var root: TreeNode ? ;
	constructor()
	{
		this.root = TreeNode();
	}
	fun insert(text: String): Unit
	{
		// First get the length of text
		val length: Int = text.length;
		// This variable are used to task find the index location of character
		var index: Int ;
		// Get the root node
		var head: TreeNode ? = this.root;
		var level: Int = 0;
		while (level < length)
		{
			// Get the index
			index = text.get(level).toInt() - 'a'.toInt();
			if (head!!.children[index] == null)
			{
				// When need to add new Node
				head.children[index] = TreeNode();
			}
			else
			{
				head.children[index]!!.count += 1;
			}
			head = head.children[index];
			level += 1;
		}
		if (head != null)
		{
			// indicates end of string
			head.last = true;
		}
	}
	fun shortestPrefix(head: TreeNode ? , output : String): Unit
	{
		if (head != null)
		{
			var i: Int = 0;
			while (i < 26)
			{
				if (head.children[i] != null)
				{
					if (head.children[i]!!.count == 1)
					{
						// Display Result
						println(output + ((i + 97).toChar()));
					}
					else
					{
						// Find short prefix
						this.shortestPrefix(head.children[i], 
                          output + ((i + 97).toChar()).toString());
					}
				}
				i += 1;
			}
		}
	}
}
fun main(args: Array < String > ): Unit
{
	// Make Tree
	val task: Trie = Trie();
	// Add word
	task.insert("bring");
	task.insert("workout");
	task.insert("break");
	task.insert("word");
	task.insert("works");
	task.insert("wordlike");
	task.insert("bress");
	// Test
	// ----
	// ➀ ["bring","break","bress"] this start with "br"
	//   Scan "br"
	//  "bring"
	//   --
	//      
	//  "break"  
	//   --│    
	//     ↓      
	//  "bress"   unique["bri", "brea","bres"]
	//   --       Note "bre" common in ["break","bress"]
	// ------------------------------------------------------
	//                    -      -      -
	// ➁ ["word","wordlike",workout","works"] this start with "wor"
	//  Scan "wor"
	//  "word" 
	//   ---│
	//      ↓
	//  "wordlike"
	//            Common in both is "word" unique ["wordl"]
	//            Note not taken "word" because after d no character
	//  "workout"
	//   ---│
	//      ↓
	//  "works"
	//        Common in both is "work" unique ["worko","works"]   
	// ------------------------------------------------------
	// Result :  [ "brea", "bres", "bri", "wordl", "worko", "works"]
	task.shortestPrefix(task.root, "");
}

Output

brea
bres
bri
wordl
worko
works

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