LintCode 链表排序[通俗易懂]

/** * Definition of ListNode * class ListNode { * public: * int val; * ListNode *next; * ListNode(int val) { * this->val = val; * this->next = NULL; * } * } */
class Solution { 
   
public:
    /** * @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

int a[1000005];
int top=0;
while(head!=NULL)
{
    a[top++]=head->val;
    head=head->next;
}
sort(a,a+top);
ListNode *dummy,*r,*s;
dummy=new ListNode(0);
r=dummy;
for(int i=0;i<top;i++)
{
    s=new ListNode(a[i]);
    r->next=s;
    r=s;
}
return dummy->next;

    }
};