合并两个有序列表

题目

力扣链接：合并两个有序链表

代码

package com.harrison.class06;

/** * @author Harrison * @create 2022-06-19-17:09 * @motto 众里寻他千百度，蓦然回首，那人却在灯火阑珊处。 */
public class Code09_MergeTwoSortedLists {
    
    public class ListNode {
    
        int val;
        ListNode next;

        ListNode() {
    
        }

        ListNode(int val) {
    
            this.val = val;
        }

        ListNode(int val, ListNode next) {
    
            this.val = val;
            this.next = next;
        }
    }


    public ListNode mergeTwoLists(ListNode head1, ListNode head2) {
    
        if(head1==null || head2==null){
    
            return head1==null?head2:head1;
        }
        ListNode head=head1.val<=head2.val?head1:head2;
        ListNode cur1=head.next;
        ListNode cur2=head==head1?head2:head1;
        ListNode pre=head;
        while(cur1!=null && cur2!=null){
    
            if(cur1.val<=cur2.val){
    
                pre.next=cur1;
                cur1=cur1.next;
            }else{
    
                pre.next=cur2;
                cur2=cur2.next;
            }
            pre=pre.next;
        }
        pre.next=cur1!=null?cur1:cur2;
        return head;
    }
}