package com.fishercoder.common.utils; import com.fishercoder.common.classes.ListNode; import java.util.List; public class LinkedListUtils { public static ListNode contructLinkedList(int[] nums) { if (nums == null || nums.length == 0) { return null; } ListNode pre = new ListNode(-1); ListNode head = new ListNode(nums[0]); pre.next = head; for (int i = 1; i < nums.length; i++) { head.next = new ListNode(nums[i]); head = head.next; } return pre.next; } public static void printList(ListNode head) { ListNode temp = head; System.out.println(); while (temp != null) { System.out.print(temp.val() + "\t"); temp = temp.next; } System.out.println(); } public static ListNode createSinglyLinkedList(List<Integer> listValues) { if (listValues == null || listValues.size() == 0) { throw new IllegalArgumentException( "Please pass in a valid listValues to create a singly linked list."); } ListNode head = new ListNode(listValues.get(0)); ListNode tmp = head; for (int i = 1; i < listValues.size(); i++) { ListNode next = new ListNode(listValues.get(i)); tmp.next = next; tmp = tmp.next; } return head; } }