标签：its pre tor des 分治法 new exit nal sorted
算法描述：
Merge k sorted linked lists and return it as one sorted list. Analyze and describe its complexity.
Example:
Input: [ 1->4->5, 1->3->4, 2->6 ] Output: 1->1->2->3->4->4->5->6
解题思路：分治法。
ListNode* mergeKLists(vector<ListNode*>& lists) { if(lists.size()==0) return nullptr; int left = 0; int right = lists.size()-1; return sortMerge(lists, left, right); } ListNode* sortMerge(vector<ListNode*>& list, int left, int right){ if(left == right) return list[left]; int mid = left + (right - left) / 2; ListNode* l1 = sortMerge(list, left, mid); ListNode* l2 = sortMerge(list, mid+1, right); return merge(l1,l2); } ListNode* merge(ListNode* l1, ListNode* l2){ ListNode* dup = new ListNode(-1); ListNode* cur = dup; while(l1!=nullptr&&l2!=nullptr){ if(l1->val < l2->val){ cur->next = l1; l1=l1->next; }else{ cur->next = l2; l2=l2->next; } cur=cur->next; } if(l1!=nullptr) cur->next = l1; if(l2!=nullptr) cur->next = l2; return dup->next; }
LeetCode-23-Merge k Sorted Lists
标签：its pre tor des 分治法 new exit nal sorted
原文地址：https://www.cnblogs.com/nobodywang/p/10361141.html
