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Longest palindromic subsequence using recursion

Here given code implementation process.

/*
    C program for
    Longest palindromic subsequence using recursion
*/
#include <stdio.h>
#include <string.h>

// Returns the max value of given two numbers
int maxValue(int a, int b)
{
	if (a > b)
	{
		return a;
	}
	return b;
}
int findLPS(char *text, int start, int ends)
{
	if (start == ends)
	{
		// When single character remains
		return 1;
	}
	if (text[start] == text[ends] && start + 1 == ends)
	{
		// When two consecutive elements are same character
		return 2;
	}
	if (text[start] == text[ends])
	{
		// Increase start value and reduce end value 
		// and find the recursively  lps
		return findLPS(text, start + 1, ends - 1) + 2;
	}
	return maxValue(findLPS(text, start, ends - 1), findLPS(text, start + 1, ends));
}
int main(int argc, char
	const *argv[])
{
	char *text1 = "pewmoozdp";
	char *text2 = "xbfdsafx";
	// Test A
	int n = strlen(text1);
	// "poop" is resultant palindrome
	// Length 4
	int ans = findLPS(text1, 0, n - 1);
	printf("\n Given  : %s ", text1);
	printf("\n Result : %d", ans);
	// Test B
	n = strlen(text2);
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = findLPS(text2, 0, n - 1);
	printf("\n Given  : %s ", text2);
	printf("\n Result : %d", ans);
	return 0;
}

Output

 Given  : pewmoozdp
 Result : 4
 Given  : xbfdsafx
 Result : 5
/*
    Java program for
    Longest palindromic subsequence using recursion
*/
public class LPS
{
    // Returns the max value of given two numbers
    public int maxValue(int a, int b)
    {
        if (a > b)
        {
            return a;
        }
        return b;
    }
    public int findLPS(String text, int start, int ends)
    {
        if (start == ends)
        {
            // When single character remains
            return 1;
        }
        if (text.charAt(start) == text.charAt(ends) && start + 1 == ends)
        {
            // When two consecutive elements are same character
            return 2;
        }
        if (text.charAt(start) == text.charAt(ends))
        {
            // Increase start value and reduce end value 
            // and find the recursively lps
            return findLPS(text, start + 1, ends - 1) + 2;
        }
        return maxValue(findLPS(text, start, ends - 1), 
                        findLPS(text, start + 1, ends));
    }
    public static void main(String[] args)
    {
        LPS task = new LPS();
        String text1 = "pewmoozdp";
        String text2 = "xbfdsafx";
        // Test A
        int n = text1.length();
        // "poop" is resultant palindrome
        // Length 4
        int ans = task.findLPS(text1, 0, n - 1);
        System.out.print("\n Given : " + text1 );
        System.out.print("\n Result : " + ans);
        // Test B
        n = text2.length();
        // [xfsfx,xfdfx,xfafx] is resultant palindrome
        // Length 5
        ans = task.findLPS(text2, 0, n - 1);
        System.out.print("\n Given : " + text2 );
        System.out.print("\n Result : " + ans );

    }
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
// Include header file
#include <iostream>
#include <string>

using namespace std;
/*
    C++ program for
    Longest palindromic subsequence using recursion
*/
class LPS
{
	public:
		// Returns the max value of given two numbers
		int maxValue(int a, int b)
		{
			if (a > b)
			{
				return a;
			}
			return b;
		}
	int findLPS(string text, int start, int ends)
	{
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text[start] == text[ends] && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text[start] == text[ends])
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return this->findLPS(text, start + 1, ends - 1) + 2;
		}
		return this->maxValue(this->findLPS(text, start, ends - 1), this->findLPS(text, start + 1, ends));
	}
};
int main()
{
	LPS *task = new LPS();
	string text1 = "pewmoozdp";
	string text2 = "xbfdsafx";
	// Test A
	int n = text1.length();
	// "poop" is resultant palindrome
	// Length 4
	int ans = task->findLPS(text1, 0, n - 1);
	cout << "\n Given : " << text1;
	cout << "\n Result : " << ans;
	// Test B
	n = text2.length();
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = task->findLPS(text2, 0, n - 1);
	cout << "\n Given : " << text2;
	cout << "\n Result : " << ans;
	return 0;
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
// Include namespace system
using System;
/*
    Csharp program for
    Longest palindromic subsequence using recursion
*/
public class LPS
{
	// Returns the max value of given two numbers
	public int maxValue(int a, int b)
	{
		if (a > b)
		{
			return a;
		}
		return b;
	}
	public int findLPS(String text, int start, int ends)
	{
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text[start] == text[ends] && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text[start] == text[ends])
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return this.findLPS(text, start + 1, ends - 1) + 2;
		}
		return this.maxValue(this.findLPS(text, start, ends - 1), this.findLPS(text, start + 1, ends));
	}
	public static void Main(String[] args)
	{
		LPS task = new LPS();
		String text1 = "pewmoozdp";
		String text2 = "xbfdsafx";
		// Test A
		int n = text1.Length;
		// "poop" is resultant palindrome
		// Length 4
		int ans = task.findLPS(text1, 0, n - 1);
		Console.Write("\n Given : " + text1);
		Console.Write("\n Result : " + ans);
		// Test B
		n = text2.Length;
		// [xfsfx,xfdfx,xfafx] is resultant palindrome
		// Length 5
		ans = task.findLPS(text2, 0, n - 1);
		Console.Write("\n Given : " + text2);
		Console.Write("\n Result : " + ans);
	}
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
package main
import "fmt"
/*
    Go program for
    Longest palindromic subsequence using recursion
*/

// Returns the max value of given two numbers
func maxValue(a, b int) int {
	if a > b {
		return a
	}
	return b
}
func findLPS(text string, start int, ends int) int {
	if start == ends {
		// When single character remains
		return 1
	}
	if text[start] == text[ends] && start + 1 == ends {
		// When two consecutive elements are same character
		return 2
	}
	if text[start] == text[ends] {
		// Increase start value and reduce end value 
		// and find the recursively lps
		return findLPS(text, start + 1, ends - 1) + 2
	}
	return maxValue(findLPS(text, start, ends - 1), findLPS(text, start + 1, ends))
}
func main() {

	var text1 string = "pewmoozdp"
	var text2 string = "xbfdsafx"
	// Test A
	var n int = len(text1)
	// "poop" is resultant palindrome
	// Length 4
	var ans int = findLPS(text1, 0, n - 1)
	fmt.Print("\n Given : ", text1)
	fmt.Print("\n Result : ", ans)
	// Test B
	n = len(text2)
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = findLPS(text2, 0, n - 1)
	fmt.Print("\n Given : ", text2)
	fmt.Print("\n Result : ", ans)
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
<?php
/*
    Php program for
    Longest palindromic subsequence using recursion
*/
class LPS
{
	// Returns the max value of given two numbers
	public	function maxValue($a, $b)
	{
		if ($a > $b)
		{
			return $a;
		}
		return $b;
	}
	public	function findLPS($text, $start, $ends)
	{
		if ($start == $ends)
		{
			// When single character remains
			return 1;
		}
		if ($text[$start] == $text[$ends] && $start + 1 == $ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if ($text[$start] == $text[$ends])
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return $this->findLPS($text, $start + 1, $ends - 1) + 2;
		}
		return $this->maxValue($this->findLPS($text, $start, $ends - 1), 
                               $this->findLPS($text, $start + 1, $ends));
	}
}

function main()
{
	$task = new LPS();
	$text1 = "pewmoozdp";
	$text2 = "xbfdsafx";
	// Test A
	$n = strlen($text1);
	// "poop" is resultant palindrome
	// Length 4
	$ans = $task->findLPS($text1, 0, $n - 1);
	echo("\n Given : ".$text1);
	echo("\n Result : ".$ans);
	// Test B
	$n = strlen($text2);
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	$ans = $task->findLPS($text2, 0, $n - 1);
	echo("\n Given : ".$text2);
	echo("\n Result : ".$ans);
}
main();

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
/*
    Node JS program for
    Longest palindromic subsequence using recursion
*/
class LPS
{
	// Returns the max value of given two numbers
	maxValue(a, b)
	{
		if (a > b)
		{
			return a;
		}
		return b;
	}
	findLPS(text, start, ends)
	{
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text.charAt(start) == text.charAt(ends) && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text.charAt(start) == text.charAt(ends))
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return this.findLPS(text, start + 1, ends - 1) + 2;
		}
		return this.maxValue(this.findLPS(text, start, ends - 1), 
                             this.findLPS(text, start + 1, ends));
	}
}

function main()
{
	var task = new LPS();
	var text1 = "pewmoozdp";
	var text2 = "xbfdsafx";
	// Test A
	var n = text1.length;
	// "poop" is resultant palindrome
	// Length 4
	var ans = task.findLPS(text1, 0, n - 1);
	process.stdout.write("\n Given : " + text1);
	process.stdout.write("\n Result : " + ans);
	// Test B
	n = text2.length;
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = task.findLPS(text2, 0, n - 1);
	process.stdout.write("\n Given : " + text2);
	process.stdout.write("\n Result : " + ans);
}
main();

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
#    Python 3 program for
#    Longest palindromic subsequence using recursion
class LPS :
	#  Returns the max value of given two numbers
	def maxValue(self, a, b) :
		if (a > b) :
			return a
		return b
	
	def findLPS(self, text, start, ends) :
		if (start == ends) :
			#  When single character remains
			return 1
		
		if (text[start] == text[ends] and start + 1 == ends) :
			#  When two consecutive elements are same character
			return 2
		
		if (text[start] == text[ends]) :
			#  Increase start value and reduce end value 
			#  and find the recursively lps
			return self.findLPS(text, start + 1, ends - 1) + 2
		
		return self.maxValue(self.findLPS(text, start, ends - 1),
                             self.findLPS(text, start + 1, ends))
	

def main() :
	task = LPS()
	text1 = "pewmoozdp"
	text2 = "xbfdsafx"
	#  Test A
	n = len(text1)
	#  "poop" is resultant palindrome
	#  Length 4
	ans = task.findLPS(text1, 0, n - 1)
	print("\n Given : ", text1, end = "")
	print("\n Result : ", ans, end = "")
	#  Test B
	n = len(text2)
	#  [xfsfx,xfdfx,xfafx] is resultant palindrome
	#  Length 5
	ans = task.findLPS(text2, 0, n - 1)
	print("\n Given : ", text2, end = "")
	print("\n Result : ", ans, end = "")

if __name__ == "__main__": main()

Output

 Given :  pewmoozdp
 Result :  4
 Given :  xbfdsafx
 Result :  5
#    Ruby program for
#    Longest palindromic subsequence using recursion
class LPS 
	#  Returns the max value of given two numbers
	def maxValue(a, b) 
		if (a > b) 
			return a
		end

		return b
	end

	def findLPS(text, start, ends) 
		if (start == ends) 
			#  When single character remains
			return 1
		end

		if (text[start] == text[ends] && start + 1 == ends) 
			#  When two consecutive elements are same character
			return 2
		end

		if (text[start] == text[ends]) 
			#  Increase start value and reduce end value 
			#  and find the recursively lps
			return self.findLPS(text, start + 1, ends - 1) + 2
		end

		return self.maxValue(self.findLPS(text, start, ends - 1), 
                             self.findLPS(text, start + 1, ends))
	end

end

def main() 
	task = LPS.new()
	text1 = "pewmoozdp"
	text2 = "xbfdsafx"
	#  Test A
	n = text1.length
	#  "poop" is resultant palindrome
	#  Length 4
	ans = task.findLPS(text1, 0, n - 1)
	print("\n Given : ", text1)
	print("\n Result : ", ans)
	#  Test B
	n = text2.length
	#  [xfsfx,xfdfx,xfafx] is resultant palindrome
	#  Length 5
	ans = task.findLPS(text2, 0, n - 1)
	print("\n Given : ", text2)
	print("\n Result : ", ans)
end

main()

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
/*
    Scala program for
    Longest palindromic subsequence using recursion
*/
class LPS()
{
	// Returns the max value of given two numbers
	def maxValue(a: Int, b: Int): Int = {
		if (a > b)
		{
			return a;
		}
		return b;
	}
	def findLPS(text: String, start: Int, ends: Int): Int = {
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text.charAt(start) == text.charAt(ends) && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text.charAt(start) == text.charAt(ends))
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return findLPS(text, start + 1, ends - 1) + 2;
		}
		return maxValue(findLPS(text, start, ends - 1), 
                        findLPS(text, start + 1, ends));
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: LPS = new LPS();
		var text1: String = "pewmoozdp";
		var text2: String = "xbfdsafx";
		// Test A
		var n: Int = text1.length();
		// "poop" is resultant palindrome
		// Length 4
		var ans: Int = task.findLPS(text1, 0, n - 1);
		print("\n Given : " + text1);
		print("\n Result : " + ans);
		// Test B
		n = text2.length();
		// [xfsfx,xfdfx,xfafx] is resultant palindrome
		// Length 5
		ans = task.findLPS(text2, 0, n - 1);
		print("\n Given : " + text2);
		print("\n Result : " + ans);
	}
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
import Foundation;
/*
    Swift 4 program for
    Longest palindromic subsequence using recursion
*/
class LPS
{
	// Returns the max value of given two numbers
	func maxValue(_ a: Int, _ b: Int) -> Int
	{
		if (a > b)
		{
			return a;
		}
		return b;
	}
	func findLPS(_ text: [Character], _ start: Int, _ ends: Int) -> Int
	{
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text[start] == text[ends] && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text[start] == text[ends])
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return self.findLPS(text, start + 1, ends - 1) + 2;
		}
		return self.maxValue(self.findLPS(text, start, ends - 1),
                             self.findLPS(text, start + 1, ends));
	}
}
func main()
{
	let task: LPS = LPS();
	let text1: String = "pewmoozdp";
	let text2: String = "xbfdsafx";
	// Test A
	var n: Int = text1.count;
	// "poop" is resultant palindrome
	// Length 4
	var ans: Int = task.findLPS(Array(text1), 0, n - 1);
	print("\n Given : ", text1, terminator: "");
	print("\n Result : ", ans, terminator: "");
	// Test B
	n = text2.count;
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = task.findLPS(Array(text2), 0, n - 1);
	print("\n Given : ", text2, terminator: "");
	print("\n Result : ", ans, terminator: "");
}
main();

Output

 Given :  pewmoozdp
 Result :  4
 Given :  xbfdsafx
 Result :  5
/*
    Kotlin program for
    Longest palindromic subsequence using recursion
*/
class LPS
{
	// Returns the max value of given two numbers
	fun maxValue(a: Int, b: Int): Int
	{
		if (a > b)
		{
			return a;
		}
		return b;
	}
	fun findLPS(text: String, start: Int, ends: Int): Int
	{
		if (start == ends)
		{
			// When single character remains
			return 1;
		}
		if (text.get(start) == text.get(ends) && start + 1 == ends)
		{
			// When two consecutive elements are same character
			return 2;
		}
		if (text.get(start) == text.get(ends))
		{
			// Increase start value and reduce end value 
			// and find the recursively lps
			return this.findLPS(text, start + 1, ends - 1) + 2;
		}
		return this.maxValue(this.findLPS(text, start, ends - 1), this.findLPS(text, start + 1, ends));
	}
}
fun main(args: Array < String > ): Unit
{
	val task: LPS = LPS();
	val text1: String = "pewmoozdp";
	val text2: String = "xbfdsafx";
	// Test A
	var n: Int = text1.length;
	// "poop" is resultant palindrome
	// Length 4
	var ans: Int = task.findLPS(text1, 0, n - 1);
	print("\n Given : " + text1);
	print("\n Result : " + ans);
	// Test B
	n = text2.length;
	// [xfsfx,xfdfx,xfafx] is resultant palindrome
	// Length 5
	ans = task.findLPS(text2, 0, n - 1);
	print("\n Given : " + text2);
	print("\n Result : " + ans);
}

Output

 Given : pewmoozdp
 Result : 4
 Given : xbfdsafx
 Result : 5
Last updated on by Kalkicode




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