标签：while tno order 题解 sort amp int solution ==
题目：
Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST.
2
1->2->3 => / 1 3
题解：
Solution 1 ()
class Solution { public: TreeNode *sortedListToBST(ListNode *head) { if (!head) return nullptr; return sortedListToBST(head, nullptr); } TreeNode *sortedListToBST(ListNode* head, ListNode* tail) { if (head == tail) return nullptr; ListNode* mid = head, *tmp = head; while (tmp != tail && tmp->next != tail) { mid = mid->next; tmp = tmp->next->next; } TreeNode* root = new TreeNode(mid->val); root->left = sortedListToBST(head, mid); root->right = sortedListToBST(mid->next, tail); return root; } };
Solution 2 ()
class Solution { public: TreeNode* sortedListToBST(ListNode* head) { if (head == nullptr) return nullptr; ListNode* fast = head; ListNode* slow = head; ListNode* prev = nullptr; while (fast != nullptr && fast->next != nullptr) { fast = fast->next->next; prev =slow; slow = slow->next; } TreeNode* root = new TreeNode(slow->val); if (prev != nullptr) prev->next = nullptr; else head = nullptr; root->left = sortedListToBST(head); root->right = sortedListToBST(slow->next); return root; } };
【Lintcode】106.Convert Sorted List to Balanced BST
标签：while tno order 题解 sort amp int solution ==
原文地址：http://www.cnblogs.com/Atanisi/p/6849156.html
