将两个线性链表合并成一个线性链表并返回

以下是将两个线性链表合并成一个线性链表并返回的代码示例：

class ListNode:
    def __init__(self, val=0, next=None):
        self.val = val
        self.next = next

def mergeTwoLists(l1: ListNode, l2: ListNode) -> ListNode:
    dummy = ListNode(0)
    curr = dummy
    
    while l1 and l2:
        if l1.val < l2.val:
            curr.next = l1
            l1 = l1.next
        else:
            curr.next = l2
            l2 = l2.next
        curr = curr.next
    
    if l1:
        curr.next = l1
    else:
        curr.next = l2
    
    return dummy.next

这段代码可以将两个有序的线性链表合并成一个有序的线性链表，并返回合并后的链表头节点。