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Longest palindromic substring manacher's algorithm

Here given code implementation process.

/*
    C program for
    Longest palindromic substring manacher's algorithm
*/
#include <stdio.h>
#include <string.h>

void findLPS(char *text)
{
	// Get length of text
	int n = strlen(text);
	if (n == 0)
	{
		// When text is empty
		return;
	}
	// When text not empty
	// Increase n value
	n = (2 *n) + 1;
	// Declare some auxiliary variables    
	int left = 0;
	int center = 1;
	int right = 2;
	int diff = -1;
	int expand = -1;
	int length = 0;
	int point = 0;
	int start = -1;
	int end = -1;
	int lps[n];
	// Set initial two starting value
	lps[0] = 0;
	lps[1] = 1;
	for (int i = 2; i < n; i++)
	{
		left = 2 *center - i;
		expand = 0;
		diff = right - i;
		if (diff >= 0)
		{
			if (lps[left] < diff)
			{
				lps[i] = lps[left];
			}
			else if (lps[left] == diff && right == n - 1)
			{
				lps[i] = lps[left];
			}
			else if (lps[left] == diff && right < n - 1)
			{
				lps[i] = lps[left];
				expand = 1;
			}
			else if (lps[left] > diff)
			{
				lps[i] = diff;
				expand = 1;
			}
		}
		else
		{
			lps[i] = 0;
			expand = 1;
		}
		if (expand == 1)
		{
			while (((i + lps[i] + 1) < n && 
                    (i - lps[i]) > 0) && 
                   (((i + lps[i] + 1) % 2 == 0) || 
                    (text[(i + lps[i] + 1) / 2] == text[(i - lps[i] - 1) / 2])))
			{
				lps[i]++;
			}
		}
		if (lps[i] > length)
		{
			length = lps[i];
			point = i;
		}
		if (i + lps[i] > right)
		{
			center = i;
			right = i + lps[i];
		}
	}
	start = (point - length) / 2;
	// Display given text
	printf("\n Given string : %s", text);
	printf("\n Result : ");
	// Display resultant palindrome
	for (int i = start; i <= start + length - 1; ++i)
	{
		printf("%c", text[i]);
	}
	// Display length of resultant palindrome
	printf("\n Resultant length : %d", length);
}
int main(int argc, char
	const *argv[])
{
	// Test
	// iiii
	findLPS("nitiiiigi");
	// ivfvi
	findLPS("vvvvivfvim");
	// civic
	findLPS("xyzacivicxrs");
	// opo
	findLPS("ttoopo");
	return 0;
}

Output

 Given string : nitiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
// Java program for
// Longest palindromic substring manacher's algorithm
public class LongestPalindrome
{
    public void findLPS(String text)
    {
        // Get length of text
        int n = text.length();
        if (n == 0)
        {
            // When text is empty
            return;
        }
        // When text not empty
        // Increase n value
        n = (2 * n) + 1;
        // Declare some auxiliary variables    
        int left = 0;
        int center = 1;
        int right = 2;
        int diff = -1;
        int expand = -1;
        int length = 0;
        int point = 0;
        int start = -1;
        int end = -1;
        int[] lps = new int[n];
        // Set initial two starting value
        lps[0] = 0;
        lps[1] = 1;
        for (int i = 2; i < n; i++)
        {
            left = 2 * center - i;
            expand = 0;
            diff = right - i;
            if (diff >= 0)
            {
                if (lps[left] < diff)
                {
                    lps[i] = lps[left];
                }
                else if (lps[left] == diff && right == n - 1)
                {
                    lps[i] = lps[left];
                }
                else if (lps[left] == diff && right < n - 1)
                {
                    lps[i] = lps[left];
                    expand = 1;
                }
                else if (lps[left] > diff)
                {
                    lps[i] = diff;
                    expand = 1;
                }
            }
            else
            {
                lps[i] = 0;
                expand = 1;
            }
            if (expand == 1)
            {
                while (((i + lps[i] + 1) < n && ((i - lps[i]) > 0)) && 
                    (((i + lps[i] + 1) % 2 == 0) || 
                    (text.charAt((i + lps[i] + 1) / 2) == 
                        text.charAt((i - lps[i] - 1) / 2))))
                {
                    lps[i]++;
                }
            }
            if (lps[i] > length)
            {
                length = lps[i];
                point = i;
            }
            if (i + lps[i] > right)
            {
                center = i;
                right = i + lps[i];
            }
        }
        start = (point - length) / 2;
        // Display given text
        System.out.print("\n Given string : " + text );
        System.out.print("\n Result : ");
        // Display resultant palindrome
        for (int i = start; i <= start + length - 1; ++i)
        {
            System.out.print(text.charAt(i) );
        }
        // Display length of resultant palindrome
        System.out.print("\n Resultant length : " + length);
    }
    public static void main(String[] args)
    {
        LongestPalindrome task = new LongestPalindrome();
        // Test
        // iiii
        task.findLPS("itiiiigi");
        // ivfvi
        task.findLPS("vvvvivfvim");
        // civic
        task.findLPS("xyzacivicxrs");
        // opo
        task.findLPS("ttoopo");
    }
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
// Include header file
#include <iostream>
#include <string>

using namespace std;
// C++ program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome
{
	public: void findLPS(string text)
	{
		// Get length of text
		int n = text.length();
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 *n) + 1;
		// Declare some auxiliary variables    
		int left = 0;
		int center = 1;
		int right = 2;
		int diff = -1;
		int expand = -1;
		int length = 0;
		int point = 0;
		int start = -1;
		int end = -1;
		int lps[n];
		// Set initial two starting value
		lps[0] = 0;
		lps[1] = 1;
		for (int i = 2; i < n; i++)
		{
			left = 2 *center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps[left] < diff)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right == n - 1)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right < n - 1)
				{
					lps[i] = lps[left];
					expand = 1;
				}
				else if (lps[left] > diff)
				{
					lps[i] = diff;
					expand = 1;
				}
			}
			else
			{
				lps[i] = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps[i] + 1) < n && ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text[(i + lps[i] + 1) / 2] == text[(i - lps[i] - 1) / 2])))
				{
					lps[i]++;
				}
			}
			if (lps[i] > length)
			{
				length = lps[i];
				point = i;
			}
			if (i + lps[i] > right)
			{
				center = i;
				right = i + lps[i];
			}
		}
		start = (point - length) / 2;
		// Display given text
		cout << "\n Given string : " << text;
		cout << "\n Result : ";
		// Display resultant palindrome
		for (int i = start; i <= start + length - 1; ++i)
		{
			cout << text[i];
		}
		// Display length of resultant palindrome
		cout << "\n Resultant length : " << length;
	}
};
int main()
{
	LongestPalindrome *task = new LongestPalindrome();
	// Test
	// iiii
	task->findLPS("itiiiigi");
	// ivfvi
	task->findLPS("vvvvivfvim");
	// civic
	task->findLPS("xyzacivicxrs");
	// opo
	task->findLPS("ttoopo");
	return 0;
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
// Include namespace system
using System;
// Csharp program for
// Longest palindromic substring manacher's algorithm
public class LongestPalindrome
{
	public void findLPS(String text)
	{
		// Get length of text
		int n = text.Length;
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 * n) + 1;
		// Declare some auxiliary variables    
		int left = 0;
		int center = 1;
		int right = 2;
		int diff = -1;
		int expand = -1;
		int length = 0;
		int point = 0;
		int start = -1;
		int[] lps = new int[n];
		// Set initial two starting value
		lps[0] = 0;
		lps[1] = 1;
		for (int i = 2; i < n; i++)
		{
			left = 2 * center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps[left] < diff)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right == n - 1)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right < n - 1)
				{
					lps[i] = lps[left];
					expand = 1;
				}
				else if (lps[left] > diff)
				{
					lps[i] = diff;
					expand = 1;
				}
			}
			else
			{
				lps[i] = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps[i] + 1) < n && ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text[(i + lps[i] + 1) / 2] == text[(i - lps[i] - 1) / 2])))
				{
					lps[i]++;
				}
			}
			if (lps[i] > length)
			{
				length = lps[i];
				point = i;
			}
			if (i + lps[i] > right)
			{
				center = i;
				right = i + lps[i];
			}
		}
		start = (point - length) / 2;
		// Display given text
		Console.Write("\n Given string : " + text);
		Console.Write("\n Result : ");
		// Display resultant palindrome
		for (int i = start; i <= start + length - 1; ++i)
		{
			Console.Write(text[i]);
		}
		// Display length of resultant palindrome
		Console.Write("\n Resultant length : " + length);
	}
	public static void Main(String[] args)
	{
		LongestPalindrome task = new LongestPalindrome();
		// Test
		// iiii
		task.findLPS("itiiiigi");
		// ivfvi
		task.findLPS("vvvvivfvim");
		// civic
		task.findLPS("xyzacivicxrs");
		// opo
		task.findLPS("ttoopo");
	}
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
package main
import "fmt"
// Go program for
// Longest palindromic substring manacher's algorithm

func findLPS(text string) {
	// Get length of text
	var n int = len(text)
	if n == 0 {
		// When text is empty
		return
	}
	// When text not empty
	// Increase n value
	n = (2 * n) + 1
	// Declare some auxiliary variables    
	var left int = 0
	var center int = 1
	var right int = 2
	var diff int = -1
	var expand int = -1
	var length int = 0
	var point int = 0
	var start int = -1
	var lps = make([] int, n)
	// Set initial two starting value
	lps[0] = 0
	lps[1] = 1
	for i := 2 ; i < n ; i++ {
		left = 2 * center - i
		expand = 0
		diff = right - i
		if diff >= 0 {
			if lps[left] < diff {
				lps[i] = lps[left]
			} else if lps[left] == diff && right == n - 1 {
				lps[i] = lps[left]
			} else if lps[left] == diff && right < n - 1 {
				lps[i] = lps[left]
				expand = 1
			} else if lps[left] > diff {
				lps[i] = diff
				expand = 1
			}
		} else {
			lps[i] = 0
			expand = 1
		}
		if expand == 1 {
			for (((i + lps[i] + 1) < n && ((i - lps[i]) > 0)) && (((i + lps[i] + 1) % 2 == 0) || (text[(i + lps[i] + 1) / 2] == text[(i - lps[i] - 1) / 2]))) {
				lps[i]++
			}
		}
		if lps[i] > length {
			length = lps[i]
			point = i
		}
		if i + lps[i] > right {
			center = i
			right = i + lps[i]
		}
	}
	start = (point - length) / 2
	// Display given text
	fmt.Print("\n Given string : ", text)
	fmt.Print("\n Result : ")
	// Display resultant palindrome
	for i := start ; i <= start + length - 1 ; i++ {
		fmt.Print(text[i])
	}
	// Display length of resultant palindrome
	fmt.Print("\n Resultant length : ", length)
}
func main() {
	
	// Test
	// iiii
	findLPS("itiiiigi")
	// ivfvi
	findLPS("vvvvivfvim")
	// civic
	findLPS("xyzacivicxrs")
	// opo
	findLPS("ttoopo")
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
<?php
// Php program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome
{
	public	function findLPS($text)
	{
		// Get length of text
		$n = strlen($text);
		if ($n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		$n = (2 * $n) + 1;
		// Declare some auxiliary variables    
		$left = 0;
		$center = 1;
		$right = 2;
		$diff = -1;
		$expand = -1;
		$length = 0;
		$point = 0;
		$start = -1;
		$lps = array_fill(0, $n, 0);
		// Set initial two starting value
		$lps[0] = 0;
		$lps[1] = 1;
		for ($i = 2; $i < $n; $i++)
		{
			$left = 2 * $center - $i;
			$expand = 0;
			$diff = $right - $i;
			if ($diff >= 0)
			{
				if ($lps[$left] < $diff)
				{
					$lps[$i] = $lps[$left];
				}
				else if ($lps[$left] == $diff && $right == $n - 1)
				{
					$lps[$i] = $lps[$left];
				}
				else if ($lps[$left] == $diff && $right < $n - 1)
				{
					$lps[$i] = $lps[$left];
					$expand = 1;
				}
				else if ($lps[$left] > $diff)
				{
					$lps[$i] = $diff;
					$expand = 1;
				}
			}
			else
			{
				$lps[$i] = 0;
				$expand = 1;
			}
			if ($expand == 1)
			{
				while ((($i + $lps[$i] + 1) < $n && 
                        (($i - $lps[$i]) > 0)) && 
                       ((($i + $lps[$i] + 1) % 2 == 0) || 
                        ($text[(int)(($i + $lps[$i] + 1) / 2)] == 
                         $text[(int)(($i - $lps[$i] - 1) / 2)])))
				{
					$lps[$i]++;
				}
			}
			if ($lps[$i] > $length)
			{
				$length = $lps[$i];
				$point = $i;
			}
			if ($i + $lps[$i] > $right)
			{
				$center = $i;
				$right = $i + $lps[$i];
			}
		}
		$start = (int)(($point - $length) / 2);
		// Display given text
		echo("\n Given string : ".$text);
		echo("\n Result : ");
		// Display resultant palindrome
		for ($i = $start; $i <= $start + $length - 1; ++$i)
		{
			echo($text[$i]);
		}
		// Display length of resultant palindrome
		echo("\n Resultant length : ".$length);
	}
}

function main()
{
	$task = new LongestPalindrome();
	// Test
	// iiii
	$task->findLPS("itiiiigi");
	// ivfvi
	$task->findLPS("vvvvivfvim");
	// civic
	$task->findLPS("xyzacivicxrs");
	// opo
	$task->findLPS("ttoopo");
}
main();

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
// Node JS program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome
{
	findLPS(text)
	{
		// Get length of text
		var n = text.length;
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 * n) + 1;
		// Declare some auxiliary variables    
		var left = 0;
		var center = 1;
		var right = 2;
		var diff = -1;
		var expand = -1;
		var length = 0;
		var point = 0;
		var start = -1;
		var lps = Array(n).fill(0);
		// Set initial two starting value
		lps[0] = 0;
		lps[1] = 1;
		for (var i = 2; i < n; i++)
		{
			left = 2 * center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps[left] < diff)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right == n - 1)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right < n - 1)
				{
					lps[i] = lps[left];
					expand = 1;
				}
				else if (lps[left] > diff)
				{
					lps[i] = diff;
					expand = 1;
				}
			}
			else
			{
				lps[i] = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps[i] + 1) < n && 
                        ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text.charAt(parseInt((i + lps[i] + 1) / 2)) 
                         == text.charAt(parseInt((i - lps[i] - 1) / 2)))))
				{
					lps[i]++;
				}
			}
			if (lps[i] > length)
			{
				length = lps[i];
				point = i;
			}
			if (i + lps[i] > right)
			{
				center = i;
				right = i + lps[i];
			}
		}
		start = parseInt((point - length) / 2);
		// Display given text
		process.stdout.write("\n Given string : " + text);
		process.stdout.write("\n Result : ");
		// Display resultant palindrome
		for (var i = start; i <= start + length - 1; ++i)
		{
			process.stdout.write(text.charAt(i));
		}
		// Display length of resultant palindrome
		process.stdout.write("\n Resultant length : " + length);
	}
}

function main()
{
	var task = new LongestPalindrome();
	// Test
	// iiii
	task.findLPS("itiiiigi");
	// ivfvi
	task.findLPS("vvvvivfvim");
	// civic
	task.findLPS("xyzacivicxrs");
	// opo
	task.findLPS("ttoopo");
}
main();

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
#  Python 3 program for
#  Longest palindromic substring manacher's algorithm
class LongestPalindrome :
	def findLPS(self, text) :
		#  Get length of text
		n = len(text)
		if (n == 0) :
			#  When text is empty
			return
		
		#  When text not empty
		#  Increase n value
		n = (2 * n) + 1
		#  Declare some auxiliary variables    
		left = 0
		center = 1
		right = 2
		diff = -1
		expand = -1
		length = 0
		point = 0
		start = -1
		lps = [0] * (n)
		#  Set initial two starting value
		lps[0] = 0
		lps[1] = 1
		i = 2
		while (i < n) :
			left = 2 * center - i
			expand = 0
			diff = right - i
			if (diff >= 0) :
				if (lps[left] < diff) :
					lps[i] = lps[left]
				elif (lps[left] == diff and right == n - 1) :
					lps[i] = lps[left]
				elif (lps[left] == diff and right < n - 1) :
					lps[i] = lps[left]
					expand = 1
				elif (lps[left] > diff) :
					lps[i] = diff
					expand = 1
				
			else :
				lps[i] = 0
				expand = 1
			
			if (expand == 1) :
				while (((i + lps[i] + 1) < n and 
                        ((i - lps[i]) > 0)) and 
                (((i + lps[i] + 1) % 2 == 0) or 
                 (text[int((i + lps[i] + 1) / 2)] == 
                  text[int((i - lps[i] - 1) / 2)]))) :
					lps[i] += 1
				
			
			if (lps[i] > length) :
				length = lps[i]
				point = i
			
			if (i + lps[i] > right) :
				center = i
				right = i + lps[i]
			
			i += 1
		
		start = int((point - length) / 2)
		#  Display given text
		print("\n Given string : ", text, end = "")
		print("\n Result : ", end = "")
		i = start
		#  Display resultant palindrome
		while (i <= start + length - 1) :
			print(text[i], end = "")
			i += 1
		
		#  Display length of resultant palindrome
		print("\n Resultant length : ", length, end = "")
	

def main() :
	task = LongestPalindrome()
	#  Test
	#  iiii
	task.findLPS("itiiiigi")
	#  ivfvi
	task.findLPS("vvvvivfvim")
	#  civic
	task.findLPS("xyzacivicxrs")
	#  opo
	task.findLPS("ttoopo")

if __name__ == "__main__": main()

Output

 Given string :  itiiiigi
 Result : iiii
 Resultant length :  4
 Given string :  vvvvivfvim
 Result : ivfvi
 Resultant length :  5
 Given string :  xyzacivicxrs
 Result : civic
 Resultant length :  5
 Given string :  ttoopo
 Result : opo
 Resultant length :  3
#  Ruby program for
#  Longest palindromic substring manacher's algorithm
class LongestPalindrome 
	def findLPS(text) 
		#  Get length of text
		n = text.length
		if (n == 0) 
			#  When text is empty
			return
		end

		#  When text not empty
		#  Increase n value
		n = (2 * n) + 1
		#  Declare some auxiliary variables    
		left = 0
		center = 1
		right = 2
		diff = -1
		expand = -1
		length = 0
		point = 0
		start = -1
		lps = Array.new(n) {0}
		#  Set initial two starting value
		lps[0] = 0
		lps[1] = 1
		i = 2
		while (i < n) 
			left = 2 * center - i
			expand = 0
			diff = right - i
			if (diff >= 0) 
				if (lps[left] < diff) 
					lps[i] = lps[left]
				elsif (lps[left] == diff && right == n - 1) 
					lps[i] = lps[left]
				elsif (lps[left] == diff && right < n - 1) 
					lps[i] = lps[left]
					expand = 1
				elsif (lps[left] > diff) 
					lps[i] = diff
					expand = 1
				end

			else
 
				lps[i] = 0
				expand = 1
			end

			if (expand == 1) 
				while (((i + lps[i] + 1) < n && ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text[(i + lps[i] + 1) / 2] == 
                         text[(i - lps[i] - 1) / 2]))) 
					lps[i] += 1
				end

			end

			if (lps[i] > length) 
				length = lps[i]
				point = i
			end

			if (i + lps[i] > right) 
				center = i
				right = i + lps[i]
			end

			i += 1
		end

		start = (point - length) / 2
		#  Display given text
		print("\n Given string : ", text)
		print("\n Result : ")
		i = start
		#  Display resultant palindrome
		while (i <= start + length - 1) 
			print(text[i])
			i += 1
		end

		#  Display length of resultant palindrome
		print("\n Resultant length : ", length)
	end

end

def main() 
	task = LongestPalindrome.new()
	#  Test
	#  iiii
	task.findLPS("itiiiigi")
	#  ivfvi
	task.findLPS("vvvvivfvim")
	#  civic
	task.findLPS("xyzacivicxrs")
	#  opo
	task.findLPS("ttoopo")
end

main()

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
// Scala program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome()
{
	def findLPS(text: String): Unit = {
		// Get length of text
		var n: Int = text.length();
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 * n) + 1;
		// Declare some auxiliary variables    
		var left: Int = 0;
		var center: Int = 1;
		var right: Int = 2;
		var diff: Int = -1;
		var expand: Int = -1;
		var length: Int = 0;
		var point: Int = 0;
		var start: Int = -1;
		var lps: Array[Int] = Array.fill[Int](n)(0);
		// Set initial two starting value
		lps(0) = 0;
		lps(1) = 1;
		var i: Int = 2;
		while (i < n)
		{
			left = 2 * center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps(left) < diff)
				{
					lps(i) = lps(left);
				}
				else if (lps(left) == diff && right == n - 1)
				{
					lps(i) = lps(left);
				}
				else if (lps(left) == diff && right < n - 1)
				{
					lps(i) = lps(left);
					expand = 1;
				}
				else if (lps(left) > diff)
				{
					lps(i) = diff;
					expand = 1;
				}
			}
			else
			{
				lps(i) = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps(i) + 1) < n && 
                        ((i - lps(i)) > 0)) && 
                       (((i + lps(i) + 1) % 2 == 0) || 
                        (text.charAt((i + lps(i) + 1) / 2) == 
                         text.charAt((i - lps(i) - 1) / 2))))
				{
					lps(i) += 1;
				}
			}
			if (lps(i) > length)
			{
				length = lps(i);
				point = i;
			}
			if (i + lps(i) > right)
			{
				center = i;
				right = i + lps(i);
			}
			i += 1;
		}
		start = (point - length) / 2;
		// Display given text
		print("\n Given string : " + text);
		print("\n Result : ");
		i = start;
		// Display resultant palindrome
		while (i <= start + length - 1)
		{
			print(text.charAt(i));
			i += 1;
		}
		// Display length of resultant palindrome
		print("\n Resultant length : " + length);
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var task: LongestPalindrome = new LongestPalindrome();
		// Test
		// iiii
		task.findLPS("itiiiigi");
		// ivfvi
		task.findLPS("vvvvivfvim");
		// civic
		task.findLPS("xyzacivicxrs");
		// opo
		task.findLPS("ttoopo");
	}
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
import Foundation;
// Swift 4 program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome
{
	func findLPS(_ data: String)
	{
        let text = Array(data);
		// Get length of text
		var n: Int = text.count;
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 * n) + 1;
		// Declare some auxiliary variables    
		var left: Int = 0;
		var center: Int = 1;
		var right: Int = 2;
		var diff: Int = -1;
		var expand: Int = -1;
		var length: Int = 0;
		var point: Int = 0;
		var start: Int = -1;
		var lps: [Int] = Array(repeating: 0, count: n);
		// Set initial two starting value
		lps[0] = 0;
		lps[1] = 1;
		var i: Int = 2;
		while (i < n)
		{
			left = 2 * center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps[left] < diff)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right == n - 1)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right < n - 1)
				{
					lps[i] = lps[left];
					expand = 1;
				}
				else if (lps[left] > diff)
				{
					lps[i] = diff;
					expand = 1;
				}
			}
			else
			{
				lps[i] = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps[i] + 1) < n && 
                        ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text[(i + lps[i] + 1) / 2] == 
                         text[(i - lps[i] - 1) / 2])))
				{
					lps[i] += 1;
				}
			}
			if (lps[i] > length)
			{
				length = lps[i];
				point = i;
			}
			if (i + lps[i] > right)
			{
				center = i;
				right = i + lps[i];
			}
			i += 1;
		}
		start = (point - length) / 2;
		// Display given text
		print("\n Given string : ", data, terminator: "");
		print("\n Result : ", terminator: "");
		i = start;
		// Display resultant palindrome
		while (i <= start + length - 1)
		{
			print(text[i], terminator: "");
			i += 1;
		}
		// Display length of resultant palindrome
		print("\n Resultant length : ", length, terminator: "");
	}
}
func main()
{
	let task: LongestPalindrome = LongestPalindrome();
	// Test
	// iiii
	task.findLPS("itiiiigi");
	// ivfvi
	task.findLPS("vvvvivfvim");
	// civic
	task.findLPS("xyzacivicxrs");
	// opo
	task.findLPS("ttoopo");
}
main();

Output

 Given string :  itiiiigi
 Result : iiii
 Resultant length :  4
 Given string :  vvvvivfvim
 Result : ivfvi
 Resultant length :  5
 Given string :  xyzacivicxrs
 Result : civic
 Resultant length :  5
 Given string :  ttoopo
 Result : opo
 Resultant length :  3
// Kotlin program for
// Longest palindromic substring manacher's algorithm
class LongestPalindrome
{
	fun findLPS(text: String): Unit
	{
		// Get length of text
		var n: Int = text.length;
		if (n == 0)
		{
			// When text is empty
			return;
		}
		// When text not empty
		// Increase n value
		n = (2 * n) + 1;
		// Declare some auxiliary variables    
		var left: Int ;
		var center: Int = 1;
		var right: Int = 2;
		var diff: Int ;
		var expand: Int ;
		var length: Int = 0;
		var point: Int = 0;
		var start: Int ;
		var lps: Array < Int > = Array(n)
		{
			0
		};
		// Set initial two starting value
		lps[0] = 0;
		lps[1] = 1;
		var i: Int = 2;
		while (i < n)
		{
			left = 2 * center - i;
			expand = 0;
			diff = right - i;
			if (diff >= 0)
			{
				if (lps[left] < diff)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right == n - 1)
				{
					lps[i] = lps[left];
				}
				else if (lps[left] == diff && right < n - 1)
				{
					lps[i] = lps[left];
					expand = 1;
				}
				else if (lps[left] > diff)
				{
					lps[i] = diff;
					expand = 1;
				}
			}
			else
			{
				lps[i] = 0;
				expand = 1;
			}
			if (expand == 1)
			{
				while (((i + lps[i] + 1) < n && 
                        ((i - lps[i]) > 0)) && 
                       (((i + lps[i] + 1) % 2 == 0) || 
                        (text.get((i + lps[i] + 1) / 2) == 
                         text.get((i - lps[i] - 1) / 2))))
				{
					lps[i] += 1;
				}
			}
			if (lps[i] > length)
			{
				length = lps[i];
				point = i;
			}
			if (i + lps[i] > right)
			{
				center = i;
				right = i + lps[i];
			}
			i += 1;
		}
		start = (point - length) / 2;
		// Display given text
		print("\n Given string : " + text);
		print("\n Result : ");
		i = start;
		// Display resultant palindrome
		while (i <= start + length - 1)
		{
			print(text.get(i));
			i += 1;
		}
		// Display length of resultant palindrome
		print("\n Resultant length : " + length);
	}
}
fun main(args: Array < String > ): Unit
{
	val task: LongestPalindrome = LongestPalindrome();
	// Test
	// iiii
	task.findLPS("itiiiigi");
	// ivfvi
	task.findLPS("vvvvivfvim");
	// civic
	task.findLPS("xyzacivicxrs");
	// opo
	task.findLPS("ttoopo");
}

Output

 Given string : itiiiigi
 Result : iiii
 Resultant length : 4
 Given string : vvvvivfvim
 Result : ivfvi
 Resultant length : 5
 Given string : xyzacivicxrs
 Result : civic
 Resultant length : 5
 Given string : ttoopo
 Result : opo
 Resultant length : 3
Last updated on by Kalkicode




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