48 lines
1.4 KiB
Java
48 lines
1.4 KiB
Java
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package Misc;
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import java.util.Stack;
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import DataStructures.Lists.SinglyLinkedList;
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/**
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* A simple way of knowing if a singly linked list is palindrome is to
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* push all the values into a Stack and then compare the list to popped
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* vales from the Stack.
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*
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* See more: https://www.geeksforgeeks.org/function-to-check-if-a-singly-linked-list-is-palindrome/
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*/
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public class PalindromeSinglyLinkedList {
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public static void main(String[] args) {
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SinglyLinkedList linkedList = new SinglyLinkedList();
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linkedList.insertHead(3);
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linkedList.insertNth(2, 1);
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linkedList.insertNth(1, 2);
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linkedList.insertNth(2, 3);
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linkedList.insertNth(3, 4);
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if (isPalindrome(linkedList)) {
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System.out.println("It's a palindrome list");
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} else {
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System.out.println("It's NOT a palindrome list");
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}
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}
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public static boolean isPalindrome(SinglyLinkedList linkedList) {
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boolean ret = true;
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Stack<Integer> linkedListValues = new Stack<>();
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for (int i = 0; i < linkedList.size(); i++) {
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linkedListValues.push(linkedList.getNth(i));
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}
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for (int i = 0; i < linkedList.size(); i++) {
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if (linkedList.getNth(i) != linkedListValues.pop()) {
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ret = false;
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break;
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}
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}
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return ret;
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}
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}
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