LeetCode - Partition List

题意

思路

代码

class Solution {

queue<int> qsml, qbig;

queue<ListNode *> p;

public:

ListNode *partition(ListNode *head, int x) {

if (!head) return head;

do

{

p.push(head);

if (head->val >= x) qbig.push(head->val);

else qsml.push(head->val);

head = head->next;

}while (head);

while (!p.empty())

{

ListNode *cur = p.front(); p.pop();

if (!head)

head = cur;

if (!qsml.empty())

    {

cur->val = qsml.front();

qsml.pop();

}

else

    {

cur->val = qbig.front();

qbig.pop();

}

if (!p.empty()) cur->next = p.front();

}

return head;

}

};