C 解法, 执行用时: 2ms, 内存消耗: 296KB, 提交时间: 2022-05-22

int main()
{
    int n=0;
    scanf("%d",&n);
    int arr[n];
    int i=0;
    for(i=0;i<n;i++)
    {
        scanf("%d",&arr[i]);
    }
    int *p=arr;
    int t=0;
    t=*p;
    *p=*(p+1);
    *(p+1)=t;
    t=*(p+n-1);
    *(p+n-1)=*(p+n-2);
    *(p+n-2)=t;
    for(i=0;i<n;i++)
    {
        printf("%d ",*(p+i));
    }
    return 0;
}

C 解法, 执行用时: 2ms, 内存消耗: 300KB, 提交时间: 2022-07-30

#include <stdio.h>
#include <malloc.h>
#include<stdlib.h>
typedef struct Node
{
  int data;
  struct Node* pNext ; 
} Node, *pNode;

int main()
{
    int len = 0;
    scanf("%d",&len);
    pNode phead = (pNode)malloc(sizeof(Node));
    pNode ptrail= (pNode)malloc(sizeof(Node));
	phead = ptrail;
    for(int i = 0; i < len; i++)
    {
        pNode pNew = (pNode)malloc(sizeof(Node));
        scanf("%d",&pNew->data);
        ptrail->pNext = pNew;
        pNew->pNext = NULL;
        ptrail = pNew;
    }
    int temp = 0;
    pNode p = phead->pNext;
    temp = p->data;
    p->data = p->pNext->data;
    p->pNext->data = temp;
    while(len-2 != 0)
    {
        p = p->pNext;
        len--;
    }
    temp = p->data;
    p->data = p->pNext->data;
    p->pNext->data = temp;
    pNode q = phead->pNext;
	while(q != NULL)
	{
		 printf("%d ",q->data);
		   q = q->pNext;
	}
}

C 解法, 执行用时: 2ms, 内存消耗: 300KB, 提交时间: 2022-06-30

#include <stdio.h>
#include <stdlib.h> 
typedef struct _ListNode{
    int val;
    struct _ListNode* next;
}ListNode;
 int main(void){
     int n;
     scanf("%d",&n);
     ListNode* out = (ListNode*)malloc(sizeof(ListNode));
     ListNode* temp = out;
     ListNode* temp2 = out;
     for(int i=0;i<n;i++){
         scanf("%d",&temp->val);
         temp->next = (ListNode*)malloc(sizeof(ListNode));
         temp = temp->next;
     }
     for(int i=0;i<n;i++){
         if(i==0||i==n-2){
             int temp_int = temp2->next->val;
             temp2->next->val = temp2->val;
             temp2->val = temp_int;
         }
         printf("%d ",temp2->val);
         temp2 = temp2->next;
         
         
     }
 
 }

C 解法, 执行用时: 2ms, 内存消耗: 304KB, 提交时间: 2022-03-18

#include<stdio.h>
#define N 1000
struct node
{
	int num;
	struct node* next;
};
int a[N];
int Len = sizeof(struct node);
struct node *creat(int n)
{
	struct node *head=NULL,*p1=NULL,*p2=NULL;
	p1 = (struct node*)malloc(Len);
	p1->next = NULL;
	head = p1;
	for (int i = 0; i < n; i++)
	{
		p2 = (struct node*)malloc(Len);
		p2->num = a[i];
		p1->next = p2;
		p1 = p2;
	}
	p1->next = NULL;
	return(head);
}
void list(struct node *head)
{
	struct node* p1=head;
	struct node* s = NULL;
	if (head == NULL)
	{
		printf("该链表为空无法打印");

	}
	else
	{
		s= p1->next;
		while (s != NULL)
		{
			printf("%d ", s->num);
			s =s->next;
		}
	}
}
struct node *change(struct node *head,int n)
{
	int flag;
	int i = 0;
	struct node *p1 = NULL, *p2 = NULL, *p3 = NULL;
	if (head == NULL)
	{
		printf("该链表为空无法交换\n");

	}
	else
	{
		p1 = head;
		for (i = 0; i < n; i++)
		{
			p1 = p1->next;
			if (i == 0)
			{
				flag = p1->num;
				p1->num = p1->next->num;
				p1->next->num = flag;
			}
			if (i == n - 2)
			{
				flag = p1->num;
				p1->num = p1->next->num;
				p1->next->num = flag;
			}
		}

	}
	return(head);

}
int main()
{
	int n;
	scanf("%d", &n);
	int i = 0;
	struct node *head;
	for (i = 0; i < n; i++)
	{
		scanf("%d", &a[i]);

	}
	head = creat(n);
	head = change(head,n);
	list(head);
}

C 解法, 执行用时: 2ms, 内存消耗: 308KB, 提交时间: 2022-03-09

#include <stdio.h>
#include <stdlib.h>
struct Node
{
    size_t n;
    struct Node *next;
};
void swap(size_t *a, size_t *b)
{
    size_t t = *a;
    *a = *b;
    *b = t;
}
int main()
{
    size_t n;
    struct Node list;
    list.next = NULL;
    scanf("%d", &n);
    for (struct Node *node = &list; n--; node = node->next)
    {
        node->next = (struct Node *)malloc(sizeof(struct Node));
        node->next->next = NULL;
        scanf("%lld", &node->next->n);
    }
    struct Node *l = list.next, *r = list.next->next;
    if (r)
    {
        swap(&l->n, &r->n);
        while (r->next)
        {
            l = l->next;
            r = r->next;
        }
        swap(&l->n, &r->n);
    }
    for (struct Node *node = list.next; node; node = node->next)
        printf("%lld ", node->n);
}