题目:
题解:
struct ListNode* swapPairs(struct ListNode* head) {
struct ListNode dummyHead;
dummyHead.next = head;
struct ListNode* temp = &dummyHead;
while (temp->next != NULL && temp->next->next != NULL) {
struct ListNode* node1 = temp->next;
struct ListNode* node2 = temp->next->next;
temp->next = node2;
node1->next = node2->next;
node2->next = node1;
temp = node1;
}
return dummyHead.next;
}