[23] Merge k Sorted Lists(TBD)

好吧就把今日命名為湊題數之日好了.....

湊著湊著湊了一個hard , 而我懶得再去看更多解法了(被歐飛）

簡單說就是先把mergeTwoLists 再寫一遍然後拿來用QQ

/**

* Definition for singly-linked list.

* struct ListNode {

* int val;

* struct ListNode *next;

* };

*/

struct ListNode* mergeTwoLists(struct ListNode* list1, struct ListNode* list2){

if (list1== NULL)

return list2;

if (list2==NULL)

return list1;

struct ListNode *p1,*p2, *head,*now;

p1=list1;

p2=list2;

if (p1->val < p2->val )

{

head = p1;

p1=p1->next;

}

else

{

head = p2;

p2=p2->next;

}

now = head;

while (p1!=NULL && p2!=NULL)

{

if (p1->val < p2->val )

{

now->next = p1;

p1=p1->next;

}

else

{

now->next = p2;

p2=p2->next;

}

now=now->next;

}

if (p1==NULL)

now->next =p2;

else

now->next = p1;

return head;

}

/**

* Definition for singly-linked list.

* struct ListNode {

* int val;

* struct ListNode *next;

* };

*/

struct ListNode* mergeKLists(struct ListNode** lists, int listsSize){

if (listsSize==1)

return lists[0];

struct ListNode* new = NULL;

for (int i=0;i<listsSize-1;i++)

{

new = mergeTwoLists(lists[i],lists[i+1]);

lists[i+1]=new;

}

return new;

}