// Function to convert a DLL to a Binary Tree
CNode *convDLLtoBT(CNode *pHeadC)
{
CNode *mid; // Middle point of DLL (and will be root)
CNode *subEnd; // Acts as end of left DLL
CNode *rHead; // Acts as pHead of right side DLL
// Base Case
if(pHeadC == NULL)
return NULL;
// Find middle of DLL/subDLL (root)
mid = findMiddle(pHeadC);
// Break out left DLL
if(pHeadC == mid)
pHeadC = NULL;
else
{
subEnd = mid->pPrevious;
if(subEnd != NULL)
subEnd->pNext = NULL;
}
rHead = mid->pNext; // Break out right DLL
mid->pPrevious = convDLLtoBT(pHeadC); // Recursive call for left DLL
mid->pNext = convDLLtoBT(rHead); // Recursive call for right DLL
return mid; // Return original mid as root of binary tree
}
int main()
{
int a[] = {2,3,2,2,2,2,1,5,4};
int result = findMiddle(a,9);
printf("result is %d\n",result);
getchar();
getchar();
return 0;
}
ListNode* sortList(ListNode* head) {
if(!head || !head->next) return head;
auto middle=findMiddle(head);
auto next=middle->next;
middle->next=NULL;
return merge(sortList(head), sortList(next));
}
int main(int argc, char **argv){
char array[] = "asdfasdfasdfasdf";
int *p = preProcess(array, 16);
double *pd = preProcess2(array, 16);
printf("find average 2 to 9: %d\n", findAverage(array, 16, 2, 9, p));
printf("find average 2 to 9: %d\n", findAverage2(array, 16, 2, 9, pd));
printf("find middle 2 to 9: %d\n", findMiddle(array, 16, 2, 9));
return 1;
}
void reorderList(struct ListNode* head) {
struct ListNode *p,*q;
if(!head||!head->next||!head->next->next)
return;
p=findMiddle(head);
q=reverse(p->next);
p->next=NULL;
merge(head,q);
}
bool isPalindrome(ListNode* head) {
ListNode* pMid = findMiddle(head);
ListNode* pRev = reverseLink(pMid);
for(;head!=pMid; head=head->next, pRev=pRev->next) {
if (head->val != pRev->val) {
return false;
}
}
return true;
}
int main()
{
int i;
int a[] = {1,2,3,2,2,2,5,4,2};
int result = findMiddle(a, 0, 8, 9);
printf("middle is %d\n", result);
getchar();
getchar();
return 0;
}
ListNode *sortList(ListNode *head) {
if (head == NULL || head->next == NULL)return head;
ListNode *middle = findMiddle(head);
ListNode *head2 = middle->next;
middle->next = nullptr; // 断开
ListNode *l1 = sortList(head); // 前半段排序
ListNode *l2 = sortList(head2); // 后半段排序
return mergeTwoLists(l1, l2);
}
ListNode* sortList(ListNode* head) {
if (!head || !head->next) {
return head;
}
ListNode* mid = findMiddle(head);
ListNode* right = sortList(mid->next);
mid->next = nullptr;
ListNode* left = sortList(head);
return merge(left, right);
}
void reorderList(ListNode *head) {
if (head == nullptr) {
return;
}
ListNode *mid = findMiddle(head);
ListNode *tail = reverse(mid->next);
mid->next = nullptr;
merge(head, tail);
return;
}
int findMiddle(int* a, int start, int end, int n)
{
int index;
int middle = -1;
index = partition(a, start, end);
printf("index is %d\n",index);
if(index==n/2){
middle = a[index];
}
else if(index>n/2){
end = index-1;
return findMiddle(a, start, end, n);
}
else{
start = index+1;
return findMiddle(a, start, end, n);
}
return middle;
}
/**
* @param head: The first node of linked list.
* @return: You should return the head of the sorted linked list,
using constant space complexity.
*/
ListNode *sortList(ListNode *head) {
// write your code here
if (NULL == head || NULL == head->next) {
return head;
}
ListNode *midNode = findMiddle(head);
ListNode *rList = sortList(midNode->next);
midNode->next = NULL;
ListNode *lList = sortList(head);
return mergeList(lList, rList);
}
static ListNode *sortList(ListNode *head) {
if (head == nullptr || head->next == nullptr) {
return head;
}
ListNode* midPtr = findMiddle(head);
ListNode* right = sortList(midPtr->next);
midPtr->next = nullptr;
ListNode* left = sortList(head);
return Merge(left, right);
}
bool isPalindrome(ListNode* head) {
//TC:O(n); SC:O(1)
if(!head){
return true;
}
ListNode* mid = findMiddle(head);
ListNode* tmp = mid->next;
mid->next = nullptr; //disconnect
ListNode* newHead = reverseList(tmp);
while(newHead){
if(newHead->val != head->val){
return false;
}
newHead = newHead->next;
head = head->next;
}
return true;
}
void reorderList(ListNode *head) {
if (!head) {
return;
}
ListNode *l1 = head, *cur = head;
ListNode *l2 = reverse(findMiddle(head));
bool reversed = false;
while(l1 || l2) {
if (!reversed) {
l1 = l1 ? l1->next : l1;
cur->next = l2;
} else {
l2 = l2 ? l2->next : l2;
cur->next = l1;
}
cur = cur->next;
reversed = !reversed;
}
}
int main(void) {
struct node * root = NULL;
insert(&root,1);
insert(&root,2);
insert(&root,3);
insert(&root,4);
insert(&root,5);
insert(&root,6);
insert(&root,7);
struct node * temp = root;
while(temp!=NULL){
printf("%d\n",temp->item);
temp=temp->next;
}
findMiddle(root);
return 0;
}
void reorderList(ListNode* head) {
if(!head||!head->next||!head->next->next) return;
ListNode* mid = findMiddle(head);
mid = rotateList(mid);
head = mergeList(head,mid);
}
void Touch::setContours(const vector<Point>& contours)
{
contourPoints = vector<Point>(contours);
middle = findMiddle();
area = countArea();
}