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Find the longest common prefix using Trie

Here given code implementation process.

//C++ program
//Find the Longest Common Prefix using Trie

#include<iostream>

#include<string>

#define ALPHABETS 26
using namespace std;
class Node {
  public:
    bool end;
  Node *children[ALPHABETS];
  Node() {
    this->end = false;
    for (int i = 0; i < ALPHABETS; ++i) {
      this->children[i] = NULL;
    }
  }
};
class Trie {
  public:
    Node *root;
  Trie() {
    this->root = new Node();
  }
  void insert(string text) {
    int length = text.size();
    int index = 0;
    Node *head = this->root;
    for (int level = 0; level < length; level++) {
      index = text[level] - 'a';
      if (head->children[index] == NULL) {
        head->children[index] = new Node();
      }
      head = head->children[index];
    }
    if (head != NULL) {
      head->end = true;
    }
  }
  void longestPrefix(Node *head, int same) {
    if (head != NULL) {
      int location = -1;
      bool status = true;
      for (int i = 0; i < ALPHABETS && status; i++) {
        if (head->children[i] != NULL) {
          if (location == -1) {
            location = i;
          }
          if (i != location) {
            status = false;
          }

        }
      }
      if (status == true) {
        cout << ((char)(location + 97));
        this->longestPrefix(head->children[location], same + 1);
      } else if (status == false && same == 0) {
        cout << "No Longest Prefix" << endl;
      }

    }
  }
};
int main() {
  Trie obj;
  //Insert following data
  obj.insert("cool");
  obj.insert("coder");
  obj.insert("confirm");
  obj.insert("cow");

  obj.longestPrefix(obj.root, 0);
  cout << endl;
}

Output

co

/*
  Java program
  Find the Longest Common Prefix using Trie
*/

class Node {
  //Indicates end of string
  public boolean end;

  public Node[] children;

  public Node(int size) {
    end = false;
    children = new Node[size];
  }
}
public class Trie 
{ 
  public int ALPHABETS = 26;
  public Node root; 

  public Trie()
  {
    root = new Node(ALPHABETS);
  }

  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
    Node head = 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 Node(ALPHABETS);
      }

      head = head.children[index];
    }
    if(head != null)
    {  
      //indicates end of string
      head.end = true;
    }
  }
  public void longestPrefix(Node head,int same)
  {
    if (head != null) {
      int location = -1;
      boolean status = true;
      for (int i = 0; i < ALPHABETS && status; i++) {
        if (head.children[i] != null) {
          if (location == -1) {
            location = i;
          }
          if (i != location) {
            status = false;
          }

        }
      }
      if (status == true) {
        System.out.print((char)(location+97));
        longestPrefix(head.children[location], same + 1);
      } else if (status == false && same == 0) {
       
        System.out.print("No Longest Prefix");
      }

    }
    
  }
 
  public static void main(String[] args) 
  {
    //Make object
    Trie obj = new Trie();

   
    obj.insert("cool");
    obj.insert("coder");
    obj.insert("confirm");
    obj.insert("cow");
    
    obj.longestPrefix(obj.root,0);
    System.out.println();
  }
}

Output

co

/*
  C# program
  Find the Longest Common Prefix using Trie
*/
using System;
public class Node {
	//Indicates end of string
	public Boolean end;

	public Node[] children;

	public Node(int size) {
		end = false;
		children = new Node[size];
	}
}
public class Trie 
{ 
	public int ALPHABETS = 26;
	public Node root; 

	public Trie()
	{
		root = new Node(ALPHABETS);
	}

	public void insert(String text) {
		//first get the.Length of text
		int size = text.Length;

		//This variable are used to task find the index location of character
		int index = 0;

		//get the root node
		Node head = root;

		for (int level = 0; level < size; level++) {
			//Get the index
			index = text[level] - 'a';

			if (head.children[index] == null) {
				//When need to add new Node
				head.children[index] = new Node(ALPHABETS);
			}

			head = head.children[index];
		}
		if (head != null) {
			//indicates end of string
			head.end = true;
		}
	}
	public void longestPrefix(Node head,int same)
	{
		if (head != null) {
			int location = -1;
			Boolean status = true;
			for (int i = 0; i < ALPHABETS && status; i++) {
				if (head.children[i] != null) {
					if (location == -1) {
						location = i;
					}
					if (i != location) {
						status = false;
					}

				}
			}
			if (status == true) {
				Console.Write((char)(location+97));
				longestPrefix(head.children[location], same + 1);
			} else if (status == false && same == 0) {

				Console.Write("No Longest Prefix");
			}

		}

	}

	public static void Main(String[] args) 
	{
		//Make object
		Trie obj = new Trie();


		obj.insert("cool");
		obj.insert("coder");
		obj.insert("confirm");
		obj.insert("cow");

		obj.longestPrefix(obj.root,0);
		Console.WriteLine();
	}
}

Output

co

# Ruby Program
# Find the Longest Common Prefix using Trie
class Node 
	attr_reader :end, :children
    attr_accessor :end, :children
	def initialize(size) 
		@end = false
		@children = Array.new(size){nil}
	end
end

class Trie 
	attr_reader :ALPHABETS, :root
    attr_accessor :ALPHABETS, :root
	def initialize() 
        @ALPHABETS = 26
		@root = Node.new(@ALPHABETS)
	end
	def insert(text) 
		length = text.length()
		location = 0
		head = @root
		level = 0
		while (level < length) 
			location = text[level].ord - 'a'.ord
			if (head.children[location] == nil) 
				head.children[location] = Node.new(@ALPHABETS)
			end
			head = head.children[location]
			level += 1
		end
		if (head != nil) 
			head.end = true
		end
	end
	def longestPrefix(head, same) 
		if (head != nil) 
			location = -1
			status = true
			i = 0
			while (i < @ALPHABETS and status==true) 
				if (head.children[i] != nil) 
					if (location == -1) 
						location = i
					elsif (i != location) 
						status = false
					end
				end
				i += 1
			end
			if (status == true) 
				print((location + 97).chr)
				self.longestPrefix(head.children[location], same + 1)
			elsif (status == false and same == 0) 
				print("No Longest Prefix")
			end
		end
	end
end
def main() 
	obj = Trie.new()
	obj.insert("cool")
	obj.insert("coder")
	obj.insert("confirm")
	obj.insert("cow")
	obj.longestPrefix(obj.root,0)
	print("\n")
end
main()

Output

co

# Python Program
# Find the Longest Common Prefix using Trie
class Node :

  def __init__(self, size) :
    self.end = False;
    self.children = [None]*size;
  

class Trie :
  

  def __init__(self) :
    self.ALPHABETS = 26;
    self.root = Node(self.ALPHABETS);
  
  def insert(self, text) :
    length = len(text)
    index = 0
    head = self.root
    level = 0
    while (level < length) :
      index = ord(text[level]) - ord('a')
      if (head.children[index] == None) :
        head.children[index] = Node(self.ALPHABETS)
      
      head = head.children[index]
      level += 1
    
    if (head != None) :
      head.end = True
     
  
  def longestPrefix(self, head, same) :
    if (head != None) :
      location = -1;
      status = True;
      i = 0;
      while (i < self.ALPHABETS and status) :
        if (head.children[i] != None) :
          if (location == -1) :
            location = i;
          
          if (i != location) :
            status = False;
          
        
        i += 1;
      
      if (status == True) :
        print(chr(location + 97),end="")
        self.longestPrefix(head.children[location], same + 1);
      elif (status == False and same == 0) :
        print("No Longest Prefix");
    
  
def main() :
  obj = Trie();
  obj.insert("cool");
  obj.insert("coder");
  obj.insert("confirm");
  obj.insert("cow");
  obj.longestPrefix(obj.root,0);
  print();
  

if __name__ == "__main__":
  main()

Output

co

/*
  Node JS Program
  Find the Longest Common Prefix using Trie
*/
class Node {

	constructor(size) {
		this.end = false;
		this.children =  new Array(size).fill(null);
	}
}
class Trie {
	
	constructor() {
		this.ALPHABETS = 26;
		this.root = new Node(this.ALPHABETS);
	}
	insert(text) {
		var length = text.length;
		var index = 0;
		var head = this.root;
		var level = 0;
		while (level < length) {
			index = text.charCodeAt(level) - 'a'.charCodeAt(0);;
			if (head.children[index] == null) {
				head.children[index] = new Node(this.ALPHABETS);
			}
			head = head.children[index];
			level++;
		}
		if (head != null) {
			head.end = true;
		}
	}
	longestPrefix(head, same) {
		if (head != null) {
			var location = -1;
			var status = true;
			var i = 0;
			while (i < this.ALPHABETS && status) {
				if (head.children[i] != null) {
					if (location == -1) {
						location = i;
					}
					if (i != location) {
						status = false;
					}
				}
				i++;
			}
			if (status == true) {
				process.stdout.write(String.fromCharCode(location + 97));
				this.longestPrefix(head.children[location], same + 1);
			} else
			if (status == false && same == 0) {
				process.stdout.write("No Longest Prefix");
			}
		}
	}
}

function main() {
	var obj = new Trie();
	obj.insert("cool");
	obj.insert("coder");
	obj.insert("confirm");
	obj.insert("cow");
	obj.longestPrefix(obj.root,0);
	process.stdout.write("\n");
}
main();

Output

co

<?php
/*
  Php Program
  Find the Longest Common Prefix using Trie
*/
class Node {
  public $end;
  public $children;

  function __construct($size) {
    $this->end = false;
    $this->children = array_fill(0, $size, null);
  }
}
class Trie {
  public $ALPHABETS = 26;
  public $root;

  function __construct() {
    $this->root = new Node($this->ALPHABETS);
  }
  public  function insert($text) {
    $length = strlen($text);
    $index = 0;
    $head = $this->root;
    $level = 0;
    while ($level < $length) {
      $index = ord($text[$level]) - ord('a');
      if ($head->children[$index] == null) {
        $head->children[$index] = new Node($this->ALPHABETS);
      }
      $head = $head->children[$index];
      $level++;
    }
    if ($head != null) {
      $head->end = true;
    }
  }
  public function longestPrefix($head, $same) {
    if ($head != null) {
      $location = -1;
      $status = true;
      $i = 0;
      while ($i < $this->ALPHABETS && $status) {
        if ($head->children[$i] != null) {
          if ($location == -1) {
            $location = $i;
          }
          if ($i != $location) {
            $status = false;
          }
        }
        $i++;
      }
      if ($status == true) {
        echo(chr($location + 97));
        $this->longestPrefix($head->children[$location], $same + 1);
      } else
      if ($status == false && $same == 0) {
        echo("No Longest Prefix");
      }
    }
  
  }
}
function main() {
    $obj = new Trie();
    $obj->insert("cool");
    $obj->insert("coder");
    $obj->insert("confirm");
    $obj->insert("cow");
    $obj->longestPrefix($obj->root,0);
    echo ("\n");
}
main();

Output

co

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