给定一个链表，将链表中的元素两两交换

例如，为了解决需要交换链表中存在的成对节点然后打印它的问题

Input : 1->2->3->4->5->6->NULL Output : 2->1->4->3->6->5->NULL Input : 1->2->3->4->5->NULL Output : 2->1->4->3->5->NULL Input : 1->NULL Output : 1->NULL登录后复制

示例

#include using namespace std; class Node { // node of our list public: int data; Node* next; }; void swapPairwise(Node* head){ Node* temp = head; while (temp != NULL && temp->next != NULL) { // for pairwise swap we need to have 2 nodes hence we are checking swap(temp->data, temp->next->data); // swapping the data temp = temp->next->next; // going to the next pair } } void push(Node** head_ref, int new_data){ // function to push our data in list Node* new_node = new Node(); // creating new node new_node->data = new_data; new_node->next = (*head_ref); // head is pushed inwards (*head_ref) = new_node; // our new node becomes our head } void printList(Node* node){ // utility function to print the given linked list while (node != NULL) { cout data next; } } int main(){ Node* head = NULL; push(&head, 5); push(&head, 4); push(&head, 3); push(&head, 2); push(&head, 1); cout data, head->next->data); // swapping data swapPairwise(head->next->next); // moving to the next pair } return; // else return } void push(Node** head_ref, int new_data){ // function to push our data in list Node* new_node = new Node(); // creating new node new_node->data = new_data; new_node->next = (*head_ref); // head is pushed inwards (*head_ref) = new_node; // our new node becomes our head } void printList(Node* node){ // utility function to print the given linked list while (node != NULL) { cout data next; } } int main(){ Node* head = NULL; push(&head, 5); push(&head, 4); push(&head, 3); push(&head, 2); push(&head, 1); cout