Java Program To Check If A Linked List Of Strings Forms A Palindrome
Last Updated :
22 Jun, 2022
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Given a linked list handling string data, check to see whether data is palindrome or not? Examples:
Input: a -> bc -> d -> dcb -> a -> NULL Output: True String "abcddcba" is palindrome. Input: a -> bc -> d -> ba -> NULL Output: False String "abcdba" is not palindrome.
The idea is very simple. Construct a string out of given linked list and check if the constructed string is palindrome or not.
Java
// Java Program to check if a given linked list // of strings form a palindromeimport java.util.Scanner;// Linked List nodeclass Node{ String data; Node next; Node(String d) { data = d; next = null; }}class LinkedList_Palindrome{ Node head; // A utility function to check if // str is palindrome or not boolean isPalidromeUtil(String str) { int length = str.length(); // Match characters from beginning // and end. for (int i = 0; i < length / 2; i++) if (str.charAt(i) != str.charAt(length - i - 1)) return false; return true; } // Returns true if string formed by // linked list is palindrome boolean isPalindrome() { Node node = head; // Append all nodes to form a // string String str = ""; while (node != null) { str = str.concat(node.data); node = node.next; } // Check if the formed string is // palindrome return isPalidromeUtil(str); } // Driver code public static void main(String[] args) { LinkedList_Palindrome list = new LinkedList_Palindrome(); list.head = new Node("a"); list.head.next = new Node("bc"); list.head.next.next = new Node("d"); list.head.next.next.next = new Node("dcb"); list.head.next.next.next.next = new Node("a"); System.out.println(list.isPalindrome()); }}// This code is contributed by Amit Khandelwal |
Output:
true
Time Complexity: O(n), where n is the number of nodes in the given linked list.
Auxiliary Space: O(m) where m is the length of the string formed by the linked list.
Please refer complete article on Check if a linked list of strings forms a palindrome for more details!
