leetcode21:Merge Two Sorted Lists

Merge Two Sorted Lists

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.

两个单链表的合并

package leetcode;public class leet21 {private static class ListNode{int val;ListNode next;ListNode(){}ListNode(int x){ val = x;}}public static void main(String[] args) {ListNode l0 = new leet21.ListNode();ListNode l1 = new leet21.ListNode(1);ListNode l2 = new leet21.ListNode(2);ListNode l3 = new leet21.ListNode(5);l0.next = l1;l1.next = l2;l2.next = l3;ListNode h0 = new leet21.ListNode();ListNode h1 = new leet21.ListNode(3);ListNode h2 = new leet21.ListNode(4);ListNode h3 = new leet21.ListNode(6);h0.next = h1;h1.next = h2;h2.next = h3;leet21 leet = new leet21();ListNode node = leet.mergeTwoList(l0, h0);while(node != null){System.out.println(node.val);node = node.next;}}public ListNode mergeTwoList(ListNode l1,ListNode l2){ListNode head = l1;ListNode p = l1;l1 = l1.next;l2 = l2.next;while(l1 != null && l2 !=null){if(l1.val < l2.val){p.next = l1;p = l1;l1 = l1.next;}else{p.next = l2;p = l2;l2 = l2.next;}}if(l1 == null)p.next = l2;if(l2 == null)p.next = l1;return head;}}