void walklist(node *head)
{
node *slow = head->next;//使用快慢指针
node *fast = head->next;
node *preslow = slow;//slow用于处理节点个数奇偶数的问题
if(fast->next == NULL)
{
return;
}
//fast = fast->next->next;
while(fast->next != NULL)
{
fast = fast->next->next;
preslow = slow;
if(fast == NULL)
{
break;
}
slow = slow->next;
}
//if(fast != NULL)
//{
//printf("%d\n", slow->key);
//printf("%d\n", slow->next->key);
//}
//else
//{
printf("%d\n", preslow->key);
printf("%d\n", preslow->next->key);
//}
//node *tail = preslow;
node *mid = NULL;
if(fast != NULL)
{
mid = reverselist(slow);//奇数个节点，slow相当于头节点
}
else
{
mid = reverselist(preslow);//偶数个节点
}
printlinkedlist(mid);
node *p = head->next;
mid = mid->next;
while(mid != NULL)
{
printf("%d-%d\n", p->key, mid->key);
if(p->key != mid->key)
{
printf("NO\n");
return;
}
p = p->next;
mid = mid->next;
}
printf("YES\n");
}
bool isPalindrome(ListNode* head) {
ListNode *slow=head,*fast=head;
ListNode *pre;
while(fast && fast->next){
pre=slow;
slow=slow->next;
fast=fast->next->next;
}
//split into two list
pre->next=NULL;
ListNode *newhead;
if(fast==NULL){
//even number list node
newhead=reverselist(slow);
}else{
//odd number list node
newhead=reverselist(slow->next);
}
while(head && newhead){
if(head->val != newhead->val){
return false;
}
head=head->next;
newhead=newhead->next;
}
return true;
}
ListNode *swapPairs(ListNode *head) {
if (head == nullptr) {
return nullptr;
}
ListNode dummy(-1);
ListNode *prepare = &dummy;
dummy.next = head;
int len = 0;
ListNode *cur = head;
while (cur != nullptr) {
len++;
cur = cur->next;
}
for (int i = 0; i < len; i = i + 2) {
if (len - i < 2) {
break;
}
prepare = reverselist(prepare);
}
return dummy.next;
}
void main()
{
NODE header,rev;
header=createempty();
getinputs(5,header);
displaylist(header);
rev=reverselist(header);
}
int main()
{
Node* head;
head=createlist();
assert(head!=NULL);
printlist(head);
reverselist(&head);
printf("after reverse\n");
printlist(head);
return 0;
}
t_ls *sorta(t_ls *a, int *state)
{
if (state[F] == 1)
return (reverselist(a));
else if (state[T] == 0 && state[R] == 0)
sortlist(&a, classalpha);
else if (state[T] == 0 && state[R] == 1)
sortlist(&a, classalpharev);
else if (state[T] == 1 && state[R] == 0 && state[U] == 1)
sortlist(&a, classtimeaccess);
else if (state[T] == 1 && state[R] == 1 && state[U] == 1)
sortlist(&a, classtimeaccessr);
else if (state[T] == 1 && state[R] == 0)
sortlist(&a, classtime);
else if (state[T] == 1 && state[R] == 1)
sortlist(&a, classtimerev);
return (a);
}
int main(int argc, char const *argv[])
{
struct ListNode *use;
struct ListNode *temp;
use = makelist();
for (temp = use; temp != NULL ; temp = temp->m_pNext){
printf("%d-->",temp->m_nkey);
}
printf("\n");
temp = reverselist(use);
for (; temp != NULL ; temp = temp->m_pNext){
printf("%d-->",temp->m_nkey);
}
printf("\n");
return 0;
}
