题目描述：输入两个单调递增的链表，输出两个链表合成后的链表，当然我们需要合成后的链表满足单调不减规则。 思路：傻瓜式操作，只进行值的交换。
public Node mergeTwoLists(Node head1, Node head2) { if(head1 == null) { return head2; } if(head2 == null) { return head1; } if(head1 == null && head2 == null) { return null; } Node head = new Node(); Node node = head; while(head1 != null && head2 != null) { if(head1.data > head2.data) { head.next = head2; head2 = head2.next; head = head.next; }else { head.next = head1; head1 = head1.next; head = head.next; } } while(head1 != null) { head.next = head1; head1 =head1.next; head = head.next; } while(head2 != null) { head.next = head1; head2 =head2.next; head = head.next; } return node.next; }