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# Print longest palindrome word in a sentence

• Difficulty Level : Easy
• Last Updated : 30 Jan, 2023

Given a string str, the task is to print longest palindrome word present in the string str.
Examples:

Input : Madam Arora teaches Malayalam
Output: Malayalam
Explanation: The string contains three palindrome words (i.e., Madam, Arora, Malayalam) but the length of Malayalam is greater than the other two.
Input : Welcome to GeeksforGeeks
Output : No Palindrome Word
Explanation:The string does not contain any palindrome word so the output is No Palindrome Word.

Approach:

• longestPalin() function finds the longest palindrome word by extracting every word of the string and passing it to checkPalin() function. An extra space is added in the original string to extract last word.
• checkPalin() function checks if the word is palindrome. It returns true if word is palindrome else returns false. It makes sure that empty strings are not counted as palindrome as the user may enter more than one spaces in between or at the beginning of the string.

## C++

 `/* C++ program to print longest palindrome``word in a sentence and its length*/``#include ``#include ``#include ` `using` `namespace` `std;` `// Function to check if a``// word is palindrome``bool` `checkPalin(string word)``{``    ``int` `n = word.length();` `    ``// making the check case``    ``// case insensitive``    ``// word = word.toLowerCase();``    ``transform(word.begin(), word.end(),``              ``word.begin(), ::``tolower``);` `    ``// loop to check palindrome``    ``for` `(``int` `i = 0; i < n; i++, n--)``        ``if` `(word[i] != word[n - 1])``            ``return` `false``;` `    ``return` `true``;``}` `// Function to find longest``// palindrome word``string longestPalin(string str)``{``    ` `    ``// to check last word for palindrome``    ``str = str + ``" "``;` `    ``// to store each word``    ``string longestword = ``""``, word = ``""``;` `    ``int` `length, length1 = 0;``    ``for` `(``int` `i = 0; i < str.length(); i++)``    ``{``        ``char` `ch = str[i];` `        ``// extracting each word``        ``if` `(ch != ``' '``)``            ``word = word + ch;``        ``else` `{``            ``length = word.length();``            ``if` `(checkPalin(word) &&``                       ``length > length1)``            ``{``                ``length1 = length;``                ``longestword = word;``            ``}` `            ``word = ``""``;``        ``}``    ``}` `    ``return` `longestword;``}` `// Driver code``int` `main()``{``    ``string s = ``"My name is ava and i love"``                         ``" Geeksforgeeks"``;` `    ``if` `(longestPalin(s) == ``""``)``        ``cout<<``"No Palindrome"``<<``" Word"``;``    ``else``        ``cout<

## Java

 `/*Java program to print longest palindrome``word in a sentence and its length*/` `public` `class` `GFG {` `    ``// Function to check if a``    ``// word is palindrome``    ``static` `boolean` `checkPalin(String word)``    ``{``        ``int` `n = word.length();` `        ``// making the check case``        ``// case insensitive``        ``word = word.toLowerCase();` `        ``// loop to check palindrome``        ``for` `(``int` `i = ``0``; i < n; i++, n--)``            ``if` `(word.charAt(i) !=``                       ``word.charAt(n - ``1``))``                ``return` `false``;` `        ``return` `true``;``    ``}` `    ``// Function to find longest``    ``// palindrome word``    ``static` `String longestPalin(String str)``    ``{``        ``// to check last word for palindrome``        ``str = str + ``" "``;` `        ``// to store each word``        ``String longestword = ``""``, word = ``""``;` `        ``int` `length, length1 = ``0``;``        ``for` `(``int` `i = ``0``; i < str.length(); i++)``        ``{``            ``char` `ch = str.charAt(i);` `            ``// extracting each word``            ``if` `(ch != ``' '``)``                ``word = word + ch;``            ``else` `{``                ``length = word.length();``                ``if` `(checkPalin(word) &&``                             ``length > length1)``                ``{``                    ``length1 = length;``                    ``longestword = word;``                ``}` `                ``word = ``""``;``            ``}``        ``}` `        ``return` `longestword;``    ``}` `    ``// Driver code``    ``public` `static` `void` `main(String args[])``    ``{``        ``String s = ``new` `String(``"My name is ava "``                ``+ ``"and i love Geeksforgeeks"``);` `        ``if` `(longestPalin(s) == ``""``)``            ``System.out.println(``"No Palindrome"``                            ``+ ``" Word"``);``        ``else``            ``System.out.println(longestPalin(s));``    ``}``}`

## Python3

 `# Python 3 program to print longest palindrome``# word in a sentence and its length` `# Function to check if a word is palindrome``def` `checkPalin(word):` `    ``n ``=` `len``(word)` `    ``# making the check case``    ``# case insensitive``    ``word ``=` `word.lower()` `    ``# loop to check palindrome``    ``for` `i ``in` `range``( n):``        ``if` `(word[i] !``=` `word[n ``-` `1``]):``            ``return` `False``        ``n ``-``=` `1` `    ``return` `True` `# Function to find longest``# palindrome word``def` `longestPalin(``str``):``    ` `    ``# to check last word for palindrome``    ``str` `=` `str` `+` `" "` `    ``# to store each word``    ``longestword ``=` `""``    ``word ``=` `""` `    ``length1 ``=` `0``    ``for` `i ``in` `range``(``len``(``str``)):``        ``ch ``=` `str``[i]` `        ``# extracting each word``        ``if` `(ch !``=` `' '``):``            ``word ``=` `word ``+` `ch``        ``else` `:``            ``length ``=` `len``(word)``            ``if` `(checkPalin(word) ``and``                ``length > length1):``                ``length1 ``=` `length``                ``longestword ``=` `word` `            ``word ``=` `""` `    ``return` `longestword` `# Driver code``if` `__name__ ``=``=` `"__main__"``:``    ` `    ``s ``=` `"My name is ava and i love Geeksforgeeks"` `    ``if` `(longestPalin(s) ``=``=` `""):``        ``print``(``"No Palindrome Word"``)``    ``else``:``        ``print``(longestPalin(s))` `# This code is contributed by ita_c`

## C#

 `/* C# program to print longest palindrome``word in a sentence and its length*/``using` `System;``class` `GFG``{``    ``// Function to check if a``    ``// word is palindrome``    ``static` `bool` `checkPalin(``string` `word)``    ``{``        ``int` `n = word.Length;``    ` `        ``// making the check case``        ``// case insensitive``        ``word = word.ToLower();``    ` `        ``// loop to check palindrome``        ``for` `(``int` `i = 0; i < n; i++, n--)``            ``if` `(word[i] != word[n - 1])``                ``return` `false``;``    ` `        ``return` `true``;``    ``}``    ` `    ``// Function to find longest``    ``// palindrome word``    ``static` `string` `longestPalin(``string` `str)``    ``{``        ` `        ``// to check last word for palindrome``        ``str = str + ``" "``;``    ` `        ``// to store each word``        ``string` `longestword = ``""``, word = ``""``;``    ` `        ``int` `length, length1 = 0;``        ``for` `(``int` `i = 0; i < str.Length; i++)``        ``{``            ``char` `ch = str[i];``    ` `            ``// extracting each word``            ``if` `(ch != ``' '``)``                ``word = word + ch;``            ``else` `{``                ``length = word.Length;``                ``if` `(checkPalin(word) &&``                        ``length > length1)``                ``{``                    ``length1 = length;``                    ``longestword = word;``                ``}``    ` `                ``word = ``""``;``            ``}``        ``}``    ` `        ``return` `longestword;``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `Main()``    ``{``        ``string` `s = ``"My name is ava and i"``           ``+ ``" love Geeksforgeeks"``;``    ` `        ``if` `(longestPalin(s) == ``""``)``            ``Console.Write(``"No Palindrome Word"``);``        ``else``            ``Console.Write(longestPalin(s));``    ``}``}` `// This code is contributed by Manish``// Shaw (manishshaw1)`

## Javascript

 ``

Output:

`ava`

#### Method #2:Using sorted() method in Python:

• The idea is to split the words of the string into a list .
• Traverse the list and append all palindromic words to new list
• Sort the newlist in increasing order of length of words using the sorted() method.
• Finally, print the last string present in the list.

Below is the implementation of the above approach.:

## Python3

 `# Python3 program for the above approach``def` `ispalindrome(string):``    ``if``(string ``=``=` `string[::``-``1``]):``        ``return` `True``    ``else``:``        ``return` `False` `def` `largestPalin(s):``  ` `    ``# Taking new list``    ``newlist ``=` `[]``    ` `    ``# Traverse the list``    ``for` `i ``in` `s:``        ``if``(ispalindrome(i)):``            ``newlist.append(i)``            ` `    ``# Using sorted() method``    ``s ``=` `sorted``(newlist, key``=``len``)` `    ``# Print last word``    ``print``(s[``len``(s)``-``1``])`  `# Driver Code``if` `__name__ ``=``=` `"__main__"``:` `    ``# Given string``    ``s ``=` `"My name is ava and i love Geeksforgeeks"` `    ``# Convert string to list``    ``l ``=` `list``(s.split(``" "``))` `    ``largestPalin(l)``    ` `# This code is contributed by vikkycirus`

## Javascript

 ``

Output:

`ava`

Method #3:Using filter() method in Python:

• First, the string is converted into a list of words using the re module.
• Then the filter function is applied to the list of word to, using ispalindrome function to filter out only the palindrome words.
• After max, the function is applied using the len as key to get a word with max length

## Python3

 `import` `re` `def` `ispalindrome(word):``    ``return` `word ``=``=` `word[::``-``1``]` `def` `largestPalin(s):``    ``# Convert string to list of words``    ``words ``=` `re.findall(r``'\b\w+\b'``, s)``    ``# Using filter() function to filter palindrome words``    ``palindrome_words ``=` `filter``(ispalindrome, words)``    ``# Using max() function to find the word with the maximum length``    ``largest_palindrome ``=` `max``(palindrome_words, key``=``len``)``    ``print``(largest_palindrome)` `# Driver Code``if` `__name__ ``=``=` `"__main__"``:``    ``s ``=` `"My name is ava and i love Geeksforgeeks"``    ``largestPalin(s)`

Output

`ava`

Time complexity:O(n)
Auxiliary Space:O(n)

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