diff --git a/src/main/java/com/thealgorithms/datastructures/lists/CountSinglyLinkedListRecursion.java b/src/main/java/com/thealgorithms/datastructures/lists/CountSinglyLinkedListRecursion.java index 4c1ffe9d3ea4..b58d51e7e5fe 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/CountSinglyLinkedListRecursion.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/CountSinglyLinkedListRecursion.java @@ -12,7 +12,7 @@ public class CountSinglyLinkedListRecursion extends SinglyLinkedList { * @param head the head node of the list segment being counted. * @return the count of nodes from the given head node onward. */ - private int countRecursion(Node head) { + private int countRecursion(SinglyLinkedListNode head) { return head == null ? 0 : 1 + countRecursion(head.next); } diff --git a/src/main/java/com/thealgorithms/datastructures/lists/MergeSortedSinglyLinkedList.java b/src/main/java/com/thealgorithms/datastructures/lists/MergeSortedSinglyLinkedList.java index a16b202c4505..4e99642fccd8 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/MergeSortedSinglyLinkedList.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/MergeSortedSinglyLinkedList.java @@ -42,12 +42,12 @@ public static SinglyLinkedList merge(SinglyLinkedList listA, SinglyLinkedList li throw new NullPointerException("Input lists must not be null."); } - Node headA = listA.getHead(); - Node headB = listB.getHead(); + SinglyLinkedListNode headA = listA.getHead(); + SinglyLinkedListNode headB = listB.getHead(); int size = listA.size() + listB.size(); - Node head = new Node(); - Node tail = head; + SinglyLinkedListNode head = new SinglyLinkedListNode(); + SinglyLinkedListNode tail = head; while (headA != null && headB != null) { if (headA.value <= headB.value) { tail.next = headA; diff --git a/src/main/java/com/thealgorithms/datastructures/lists/QuickSortLinkedList.java b/src/main/java/com/thealgorithms/datastructures/lists/QuickSortLinkedList.java index 08fe674b47f4..f018781ada70 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/QuickSortLinkedList.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/QuickSortLinkedList.java @@ -105,7 +105,7 @@ public class QuickSortLinkedList { private final SinglyLinkedList list; // The linked list to be sorted - private Node head; // Head of the list + private SinglyLinkedListNode head; // Head of the list /** * Constructor that initializes the QuickSortLinkedList with a given linked list. @@ -136,19 +136,19 @@ public void sortList() { * @param head The head node of the list to sort * @return The head node of the sorted linked list */ - private Node sortList(Node head) { + private SinglyLinkedListNode sortList(SinglyLinkedListNode head) { if (head == null || head.next == null) { return head; } - Node pivot = head; + SinglyLinkedListNode pivot = head; head = head.next; pivot.next = null; - Node lessHead = new Node(); - Node lessTail = lessHead; - Node greaterHead = new Node(); - Node greaterTail = greaterHead; + SinglyLinkedListNode lessHead = new SinglyLinkedListNode(); + SinglyLinkedListNode lessTail = lessHead; + SinglyLinkedListNode greaterHead = new SinglyLinkedListNode(); + SinglyLinkedListNode greaterTail = greaterHead; while (head != null) { if (head.value < pivot.value) { @@ -164,14 +164,14 @@ private Node sortList(Node head) { lessTail.next = null; greaterTail.next = null; - Node sortedLess = sortList(lessHead.next); - Node sortedGreater = sortList(greaterHead.next); + SinglyLinkedListNode sortedLess = sortList(lessHead.next); + SinglyLinkedListNode sortedGreater = sortList(greaterHead.next); if (sortedLess == null) { pivot.next = sortedGreater; return pivot; } else { - Node current = sortedLess; + SinglyLinkedListNode current = sortedLess; while (current.next != null) { current = current.next; } diff --git a/src/main/java/com/thealgorithms/datastructures/lists/ReverseKGroup.java b/src/main/java/com/thealgorithms/datastructures/lists/ReverseKGroup.java index c9a5c1df9870..9b9464d388b5 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/ReverseKGroup.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/ReverseKGroup.java @@ -14,10 +14,10 @@ *

*

* The implementation contains: - * - {@code length(Node head)}: A method to calculate the length of the linked list. - * - {@code reverse(Node head, int count, int k)}: A helper method that reverses the nodes + * - {@code length(SinglyLinkedListNode head)}: A method to calculate the length of the linked list. + * - {@code reverse(SinglyLinkedListNode head, int count, int k)}: A helper method that reverses the nodes * in the linked list in groups of k. - * - {@code reverseKGroup(Node head, int k)}: The main method that initiates the reversal + * - {@code reverseKGroup(SinglyLinkedListNode head, int k)}: The main method that initiates the reversal * process by calling the reverse method. *

*

@@ -38,8 +38,8 @@ public class ReverseKGroup { * @param head The head node of the linked list. * @return The total number of nodes in the linked list. */ - public int length(Node head) { - Node curr = head; + public int length(SinglyLinkedListNode head) { + SinglyLinkedListNode curr = head; int count = 0; while (curr != null) { curr = curr.next; @@ -56,14 +56,14 @@ public int length(Node head) { * @param k The size of the group to reverse. * @return The new head of the reversed linked list segment. */ - public Node reverse(Node head, int count, int k) { + public SinglyLinkedListNode reverse(SinglyLinkedListNode head, int count, int k) { if (count < k) { return head; } - Node prev = null; + SinglyLinkedListNode prev = null; int count1 = 0; - Node curr = head; - Node next = null; + SinglyLinkedListNode curr = head; + SinglyLinkedListNode next = null; while (curr != null && count1 < k) { next = curr.next; curr.next = prev; @@ -85,7 +85,7 @@ public Node reverse(Node head, int count, int k) { * @param k The size of the group to reverse. * @return The head of the modified linked list after reversal. */ - public Node reverseKGroup(Node head, int k) { + public SinglyLinkedListNode reverseKGroup(SinglyLinkedListNode head, int k) { int count = length(head); return reverse(head, count, k); } diff --git a/src/main/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedLists.java b/src/main/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedLists.java index 7676cc343653..47ee5397097c 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedLists.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedLists.java @@ -38,12 +38,12 @@ public class RotateSinglyLinkedLists { * @param k The number of positions to rotate the list to the right. * @return The head of the rotated linked list. */ - public Node rotateRight(Node head, int k) { + public SinglyLinkedListNode rotateRight(SinglyLinkedListNode head, int k) { if (head == null || head.next == null || k == 0) { return head; } - Node curr = head; + SinglyLinkedListNode curr = head; int len = 1; while (curr.next != null) { curr = curr.next; diff --git a/src/main/java/com/thealgorithms/datastructures/lists/SearchSinglyLinkedListRecursion.java b/src/main/java/com/thealgorithms/datastructures/lists/SearchSinglyLinkedListRecursion.java index a40e9b2a1a66..4ac2de422595 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/SearchSinglyLinkedListRecursion.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/SearchSinglyLinkedListRecursion.java @@ -30,7 +30,7 @@ public class SearchSinglyLinkedListRecursion extends SinglyLinkedList { * @param key the integer value to be searched for. * @return {@code true} if the value `key` is present in the list; otherwise, {@code false}. */ - private boolean searchRecursion(Node node, int key) { + private boolean searchRecursion(SinglyLinkedListNode node, int key) { return (node != null && (node.value == key || searchRecursion(node.next, key))); } diff --git a/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedList.java b/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedList.java index eb6cdf48f58b..ff4af4437cc7 100644 --- a/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedList.java +++ b/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedList.java @@ -12,7 +12,7 @@ public class SinglyLinkedList implements Iterable { /** * Head refer to the front of the list */ - private Node head; + private SinglyLinkedListNode head; /** * Size of SinglyLinkedList @@ -33,7 +33,7 @@ public SinglyLinkedList() { * @param head the head node of list * @param size the size of list */ - public SinglyLinkedList(Node head, int size) { + public SinglyLinkedList(SinglyLinkedListNode head, int size) { this.head = head; this.size = size; } @@ -44,8 +44,8 @@ public SinglyLinkedList(Node head, int size) { * */ public boolean detectLoop() { - Node currentNodeFast = head; - Node currentNodeSlow = head; + SinglyLinkedListNode currentNodeFast = head; + SinglyLinkedListNode currentNodeSlow = head; while (currentNodeFast != null && currentNodeFast.next != null) { currentNodeFast = currentNodeFast.next.next; currentNodeSlow = currentNodeSlow.next; @@ -61,12 +61,12 @@ public boolean detectLoop() { * If the length of the list is even then return item number length/2 * @return middle node of the list */ - public Node middle() { + public SinglyLinkedListNode middle() { if (head == null) { return null; } - Node firstCounter = head; - Node secondCounter = firstCounter.next; + SinglyLinkedListNode firstCounter = head; + SinglyLinkedListNode secondCounter = firstCounter.next; while (secondCounter != null && secondCounter.next != null) { firstCounter = firstCounter.next; secondCounter = secondCounter.next.next; @@ -82,15 +82,15 @@ public void swapNodes(int valueFirst, int valueSecond) { if (valueFirst == valueSecond) { return; } - Node previousA = null; - Node currentA = head; + SinglyLinkedListNode previousA = null; + SinglyLinkedListNode currentA = head; while (currentA != null && currentA.value != valueFirst) { previousA = currentA; currentA = currentA.next; } - Node previousB = null; - Node currentB = head; + SinglyLinkedListNode previousB = null; + SinglyLinkedListNode currentB = head; while (currentB != null && currentB.value != valueSecond) { previousB = currentB; currentB = currentB.next; @@ -117,7 +117,7 @@ public void swapNodes(int valueFirst, int valueSecond) { } // Swap next pointer - Node temp = currentA.next; + var temp = currentA.next; currentA.next = currentB.next; currentB.next = temp; } @@ -126,12 +126,12 @@ public void swapNodes(int valueFirst, int valueSecond) { * Reverse a singly linked list[Iterative] from a given node till the end * */ - public Node reverseListIter(Node node) { - Node prev = null; - Node curr = node; + public SinglyLinkedListNode reverseListIter(SinglyLinkedListNode node) { + SinglyLinkedListNode prev = null; + SinglyLinkedListNode curr = node; while (curr != null && curr.next != null) { - Node next = curr.next; + var next = curr.next; curr.next = prev; prev = curr; curr = next; @@ -149,13 +149,13 @@ public Node reverseListIter(Node node) { * Reverse a singly linked list[Recursive] from a given node till the end * */ - public Node reverseListRec(Node head) { + public SinglyLinkedListNode reverseListRec(SinglyLinkedListNode head) { if (head == null || head.next == null) { return head; } - Node prev = null; - Node h2 = reverseListRec(head.next); + SinglyLinkedListNode prev = null; + SinglyLinkedListNode h2 = reverseListRec(head.next); head.next.next = head; head.next = prev; @@ -167,7 +167,7 @@ public Node reverseListRec(Node head) { * Clear all nodes in the list */ public void clear() { - Node cur = head; + SinglyLinkedListNode cur = head; while (cur != null) { cur = cur.next; } @@ -198,7 +198,7 @@ public int size() { * * @return head of the list. */ - public Node getHead() { + public SinglyLinkedListNode getHead() { return head; } @@ -206,7 +206,7 @@ public Node getHead() { * Set head of the list. * */ - public void setHead(Node head) { + public void setHead(SinglyLinkedListNode head) { this.head = head; } @@ -249,10 +249,10 @@ public String toString() { } public void deleteDuplicates() { - Node pred = head; + SinglyLinkedListNode pred = head; // predecessor = the node // having sublist of its duplicates - Node newHead = head; + SinglyLinkedListNode newHead = head; while (newHead != null) { // if it's a beginning of duplicates sublist // skip all duplicates @@ -273,7 +273,7 @@ public void deleteDuplicates() { } public void print() { - Node temp = head; + SinglyLinkedListNode temp = head; while (temp != null && temp.next != null) { System.out.print(temp.value + "->"); temp = temp.next; @@ -310,7 +310,7 @@ public void insert(int data) { */ public void insertNth(int data, int position) { checkBounds(position, 0, size); - Node newNode = new Node(data); + SinglyLinkedListNode newNode = new SinglyLinkedListNode(data); if (head == null) { /* the list is empty */ head = newNode; @@ -325,7 +325,7 @@ public void insertNth(int data, int position) { return; } - Node cur = head; + SinglyLinkedListNode cur = head; for (int i = 0; i < position - 1; ++i) { cur = cur.next; } @@ -359,7 +359,7 @@ public void deleteNth(int position) { size--; return; } - Node cur = head; + SinglyLinkedListNode cur = head; for (int i = 0; i < position - 1; ++i) { cur = cur.next; } @@ -376,7 +376,7 @@ public void deleteNth(int position) { */ public int getNth(int index) { checkBounds(index, 0, size - 1); - Node cur = head; + SinglyLinkedListNode cur = head; for (int i = 0; i < index; ++i) { cur = cur.next; } @@ -440,7 +440,7 @@ public static void main(String[] arg) { } SinglyLinkedList instance = new SinglyLinkedList(); - Node head = new Node(0, new Node(2, new Node(3, new Node(3, new Node(4))))); + SinglyLinkedListNode head = new SinglyLinkedListNode(0, new SinglyLinkedListNode(2, new SinglyLinkedListNode(3, new SinglyLinkedListNode(3, new SinglyLinkedListNode(4))))); instance.setHead(head); instance.deleteDuplicates(); instance.print(); @@ -452,7 +452,7 @@ public Iterator iterator() { } private class SinglyLinkedListIterator implements Iterator { - private Node current; + private SinglyLinkedListNode current; SinglyLinkedListIterator() { current = head; @@ -474,43 +474,3 @@ public Integer next() { } } } - -/** - * This class is the nodes of the SinglyLinked List. They consist of a value and - * a pointer to the node after them. - */ -class Node { - - /** - * The value of the node - */ - int value; - - /** - * Point to the next node - */ - Node next; - - Node() { - } - - /** - * Constructor - * - * @param value Value to be put in the node - */ - Node(int value) { - this(value, null); - } - - /** - * Constructor - * - * @param value Value to be put in the node - * @param next Reference to the next node - */ - Node(int value, Node next) { - this.value = value; - this.next = next; - } -} diff --git a/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedListNode.java b/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedListNode.java new file mode 100644 index 000000000000..d0a06369215a --- /dev/null +++ b/src/main/java/com/thealgorithms/datastructures/lists/SinglyLinkedListNode.java @@ -0,0 +1,34 @@ +package com.thealgorithms.datastructures.lists; + +/** + * This class is the nodes of the SinglyLinked List. They consist of a value and + * a pointer to the node after them. + */ +class SinglyLinkedListNode { + + int value; + SinglyLinkedListNode next = null; + + SinglyLinkedListNode() { + } + + /** + * Constructor + * + * @param value Value to be put in the node + */ + SinglyLinkedListNode(int value) { + this(value, null); + } + + /** + * Constructor + * + * @param value Value to be put in the node + * @param next Reference to the next node + */ + SinglyLinkedListNode(int value, SinglyLinkedListNode next) { + this.value = value; + this.next = next; + } +} diff --git a/src/test/java/com/thealgorithms/datastructures/lists/ReverseKGroupTest.java b/src/test/java/com/thealgorithms/datastructures/lists/ReverseKGroupTest.java index b2db478f692c..76b7ab063de4 100644 --- a/src/test/java/com/thealgorithms/datastructures/lists/ReverseKGroupTest.java +++ b/src/test/java/com/thealgorithms/datastructures/lists/ReverseKGroupTest.java @@ -20,8 +20,8 @@ public void testReverseKGroupWithEmptyList() { @Test public void testReverseKGroupWithSingleNodeList() { ReverseKGroup reverser = new ReverseKGroup(); - Node singleNode = new Node(5); - Node result = reverser.reverseKGroup(singleNode, 2); + SinglyLinkedListNode singleNode = new SinglyLinkedListNode(5); + SinglyLinkedListNode result = reverser.reverseKGroup(singleNode, 2); assertEquals(5, result.value); assertNull(result.next); } @@ -31,15 +31,15 @@ public void testReverseKGroupWithKEqualTo2() { ReverseKGroup reverser = new ReverseKGroup(); // Create a list with multiple elements (1 -> 2 -> 3 -> 4 -> 5) - Node head; - head = new Node(1); - head.next = new Node(2); - head.next.next = new Node(3); - head.next.next.next = new Node(4); - head.next.next.next.next = new Node(5); + SinglyLinkedListNode head; + head = new SinglyLinkedListNode(1); + head.next = new SinglyLinkedListNode(2); + head.next.next = new SinglyLinkedListNode(3); + head.next.next.next = new SinglyLinkedListNode(4); + head.next.next.next.next = new SinglyLinkedListNode(5); // Test reverse with k=2 - Node result1 = reverser.reverseKGroup(head, 2); + SinglyLinkedListNode result1 = reverser.reverseKGroup(head, 2); assertEquals(2, result1.value); assertEquals(1, result1.next.value); assertEquals(4, result1.next.next.value); @@ -53,15 +53,15 @@ public void testReverseKGroupWithKEqualTo3() { ReverseKGroup reverser = new ReverseKGroup(); // Create a list with multiple elements (1 -> 2 -> 3 -> 4 -> 5) - Node head; - head = new Node(1); - head.next = new Node(2); - head.next.next = new Node(3); - head.next.next.next = new Node(4); - head.next.next.next.next = new Node(5); + SinglyLinkedListNode head; + head = new SinglyLinkedListNode(1); + head.next = new SinglyLinkedListNode(2); + head.next.next = new SinglyLinkedListNode(3); + head.next.next.next = new SinglyLinkedListNode(4); + head.next.next.next.next = new SinglyLinkedListNode(5); // Test reverse with k=3 - Node result = reverser.reverseKGroup(head, 3); + SinglyLinkedListNode result = reverser.reverseKGroup(head, 3); assertEquals(3, result.value); assertEquals(2, result.next.value); assertEquals(1, result.next.next.value); diff --git a/src/test/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedListsTest.java b/src/test/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedListsTest.java index 70c0dfccafa4..c476ad1b0203 100644 --- a/src/test/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedListsTest.java +++ b/src/test/java/com/thealgorithms/datastructures/lists/RotateSinglyLinkedListsTest.java @@ -14,24 +14,24 @@ public class RotateSinglyLinkedListsTest { private final RotateSinglyLinkedLists rotator = new RotateSinglyLinkedLists(); // Helper method to create a linked list from an array of values - private Node createLinkedList(int[] values) { + private SinglyLinkedListNode createLinkedList(int[] values) { if (values.length == 0) { return null; } - Node head = new Node(values[0]); - Node current = head; + SinglyLinkedListNode head = new SinglyLinkedListNode(values[0]); + SinglyLinkedListNode current = head; for (int i = 1; i < values.length; i++) { - current.next = new Node(values[i]); + current.next = new SinglyLinkedListNode(values[i]); current = current.next; } return head; } // Helper method to convert a linked list to a string for easy comparison - private String linkedListToString(Node head) { + private String linkedListToString(SinglyLinkedListNode head) { StringBuilder sb = new StringBuilder(); - Node current = head; + SinglyLinkedListNode current = head; while (current != null) { sb.append(current.value); if (current.next != null) { @@ -51,55 +51,55 @@ public void testRotateRightEmptyList() { @Test public void testRotateRightSingleNodeList() { // Rotate a list with a single element - Node singleNode = new Node(5); - Node rotatedSingleNode = rotator.rotateRight(singleNode, 3); + SinglyLinkedListNode singleNode = new SinglyLinkedListNode(5); + SinglyLinkedListNode rotatedSingleNode = rotator.rotateRight(singleNode, 3); assertEquals("5", linkedListToString(rotatedSingleNode)); } @Test public void testRotateRightMultipleElementsList() { // Rotate a list with multiple elements (rotate by 2) - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5}); - Node rotated = rotator.rotateRight(head, 2); + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 2); assertEquals("4 -> 5 -> 1 -> 2 -> 3", linkedListToString(rotated)); } @Test public void testRotateRightFullRotation() { // Rotate by more than the length of the list - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5}); - Node rotated = rotator.rotateRight(head, 7); + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 7); assertEquals("4 -> 5 -> 1 -> 2 -> 3", linkedListToString(rotated)); } @Test public void testRotateRightZeroRotation() { // Rotate a list by k = 0 (no rotation) - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5}); - Node rotated = rotator.rotateRight(head, 0); + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 0); assertEquals("1 -> 2 -> 3 -> 4 -> 5", linkedListToString(rotated)); } @Test public void testRotateRightByListLength() { // Rotate a list by k equal to list length (no change) - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5}); - Node rotated = rotator.rotateRight(head, 5); + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 5); assertEquals("1 -> 2 -> 3 -> 4 -> 5", linkedListToString(rotated)); } @Test public void testRotateRightByMultipleOfListLength() { - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5}); - Node rotated = rotator.rotateRight(head, 10); // k = 2 * list length + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 10); // k = 2 * list length assertEquals("1 -> 2 -> 3 -> 4 -> 5", linkedListToString(rotated)); } @Test public void testRotateRightLongerList() { // Rotate a longer list by a smaller k - Node head = createLinkedList(new int[] {1, 2, 3, 4, 5, 6, 7, 8, 9}); - Node rotated = rotator.rotateRight(head, 4); + SinglyLinkedListNode head = createLinkedList(new int[] {1, 2, 3, 4, 5, 6, 7, 8, 9}); + SinglyLinkedListNode rotated = rotator.rotateRight(head, 4); assertEquals("6 -> 7 -> 8 -> 9 -> 1 -> 2 -> 3 -> 4 -> 5", linkedListToString(rotated)); } } diff --git a/src/test/java/com/thealgorithms/datastructures/lists/SinglyLinkedListTest.java b/src/test/java/com/thealgorithms/datastructures/lists/SinglyLinkedListTest.java index a47434083cdb..f80c6b5055f0 100644 --- a/src/test/java/com/thealgorithms/datastructures/lists/SinglyLinkedListTest.java +++ b/src/test/java/com/thealgorithms/datastructures/lists/SinglyLinkedListTest.java @@ -18,9 +18,9 @@ public class SinglyLinkedListTest { * @return linked list with pre-defined number of nodes */ private SinglyLinkedList createSampleList(int length) { - List nodeList = new ArrayList<>(); + List nodeList = new ArrayList<>(); for (int i = 1; i <= length; i++) { - Node node = new Node(i); + SinglyLinkedListNode node = new SinglyLinkedListNode(i); nodeList.add(node); } @@ -34,10 +34,10 @@ private SinglyLinkedList createSampleList(int length) { @Test void detectLoop() { // List has cycle - Node firstNode = new Node(1); - Node secondNode = new Node(2); - Node thirdNode = new Node(3); - Node fourthNode = new Node(4); + SinglyLinkedListNode firstNode = new SinglyLinkedListNode(1); + SinglyLinkedListNode secondNode = new SinglyLinkedListNode(2); + SinglyLinkedListNode thirdNode = new SinglyLinkedListNode(3); + SinglyLinkedListNode fourthNode = new SinglyLinkedListNode(4); firstNode.next = secondNode; secondNode.next = thirdNode; @@ -112,13 +112,13 @@ void reverseList() { // Reversing the LinkedList using reverseList() method and storing the head of the reversed // linkedlist in a head node The reversed linkedlist will be 4->3->2->1->null - Node head = list.reverseListIter(list.getHead()); + SinglyLinkedListNode head = list.reverseListIter(list.getHead()); // Recording the Nodes after reversing the LinkedList - Node firstNode = head; // 4 - Node secondNode = firstNode.next; // 3 - Node thirdNode = secondNode.next; // 2 - Node fourthNode = thirdNode.next; // 1 + SinglyLinkedListNode firstNode = head; // 4 + SinglyLinkedListNode secondNode = firstNode.next; // 3 + SinglyLinkedListNode thirdNode = secondNode.next; // 2 + SinglyLinkedListNode fourthNode = thirdNode.next; // 1 // Checking whether the LinkedList is reversed or not by comparing the original list and // reversed list nodes @@ -134,10 +134,10 @@ void reverseList() { void reverseListNullPointer() { // Creating a linkedlist with first node assigned to null SinglyLinkedList list = new SinglyLinkedList(); - Node first = list.getHead(); + SinglyLinkedListNode first = list.getHead(); // Reversing the linkedlist - Node head = list.reverseListIter(first); + SinglyLinkedListNode head = list.reverseListIter(first); // checking whether the method works fine if the input is null assertEquals(head, first); @@ -151,10 +151,10 @@ void reverseListTest() { // Reversing the LinkedList using reverseList() method and storing the head of the reversed // linkedlist in a head node - Node head = list.reverseListIter(list.getHead()); + SinglyLinkedListNode head = list.reverseListIter(list.getHead()); // Storing the head in a temp variable, so that we cannot loose the track of head - Node temp = head; + SinglyLinkedListNode temp = head; int i = 20; // This is for the comparison of values of nodes of the reversed linkedlist // Checking whether the reverseList() method performed its task @@ -171,7 +171,7 @@ void recursiveReverseList() { SinglyLinkedList list = createSampleList(5); // Reversing the linked list using reverseList() method - Node head = list.reverseListRec(list.getHead()); + SinglyLinkedListNode head = list.reverseListRec(list.getHead()); // Check if the reversed list is: 5 -> 4 -> 3 -> 2 -> 1 assertEquals(5, head.value); @@ -185,10 +185,10 @@ void recursiveReverseList() { void recursiveReverseListNullPointer() { // Create an empty linked list SinglyLinkedList list = new SinglyLinkedList(); - Node first = list.getHead(); + SinglyLinkedListNode first = list.getHead(); // Reversing the empty linked list - Node head = list.reverseListRec(first); + SinglyLinkedListNode head = list.reverseListRec(first); // Check if the head remains the same (null) assertNull(head); @@ -200,11 +200,11 @@ void recursiveReverseListTest() { SinglyLinkedList list = createSampleList(20); // Reversing the linked list using reverseList() method - Node head = list.reverseListRec(list.getHead()); + SinglyLinkedListNode head = list.reverseListRec(list.getHead()); // Check if the reversed list has the correct values int i = 20; - Node temp = head; + SinglyLinkedListNode temp = head; while (temp != null && i > 0) { assertEquals(i, temp.value); temp = temp.next;