题解 | #删除有序链表中重复的元素-I#

package suanfa.list;

/**

• 链表删除重复

• /
  public class DeleteDuplicates {

  public static void main(String[] args) {

    ListNode listNode1 = new ListNode();
    ListNode listNode2 = new ListNode();
    ListNode listNode3 = new ListNode();
    ListNode listNode4 = new ListNode();
    ListNode listNode5 = new ListNode();
  
    listNode1.setVal(1);
    listNode1.setNext(listNode2);
  
    listNode2.setVal(2);
    listNode2.setNext(listNode3);
  
    listNode3.setVal(2);
    listNode3.setNext(listNode4);
  
    listNode4.setVal(3);
    listNode4.setNext(listNode5);
  
    listNode5.setVal(4);
  
    ListNode result = deleteDuplicates(listNode1);

  }

  public static ListNode deleteDuplicates(ListNode head) {

    ListNode current = head;
    ListNode pre = current;
    /**
     * 如果当前元素和下一个元素的值不相同，当前元素向下移动一个
     * 如果当前元素和下一个元素的值相同，当前元素向下移动两个
     */
    while (current != null && current.next != null) {
        if (current.val != current.next.val) {
            current = current.next;
        } else {
            current.next = current.next.next;
        }
    }
  
    return pre;

  }

  static class ListNode {

    int val;
    ListNode next;
  
    public int getVal() {
        return val;
    }
  
    public void setVal(int val) {
        this.val = val;
    }
  
    public ListNode getNext() {
        return next;
    }
  
    public void setNext(ListNode next) {
        this.next = next;
    }

  }
  }