1、題目
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.
合并2個(gè)有序鏈表
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2、代碼實(shí)現(xiàn)
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode mergeTwoLists(ListNode l1, ListNode l2) {
if (l1 == null) {
return l2;
}
if (l2 == null) {
return l1;
}
ListNode head = new ListNode(0);
ListNode cur = head;
while (l1 != null && l2 != null) {
if (l1.val <= l2.val) {
//cur.val = l1.val;這樣寫會(huì)爆空指針異常
cur.next = l1;
l1 = l1.next;
} else {
//cur.val = l2.val;這樣寫會(huì)爆空指針異常
cur.next = l2;
//System.out.println(head.val);
l2 = l2.next;
}
cur = cur.next;
}
if (l1 != null) {
cur.next = l1;
} else {
System.out.println("l2 != null");
cur.next = l2;
}
return head.next;
}
}
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