乘风破浪:LeetCode真题_023_Merge k Sorted Lists一、前言上次我们学过了合并两个链表,这次我们要合并N个链表要怎么做呢,最先想到的就是转换成2个链表合并的问题,然后解决,再优化一点的,就是两个两个合并,当然我们也可以一次性比较所有的元素,然后一点点的进行合并等等。
找到第一个没有重复出现的字母 Given a strings,find the first non-repeating character in it and return its index. If it does not exist, return-1. Example 1: Input: s = "leetcode" Output: 0 Example 2: Input: s = "loveleetcode" Output: 2 Example 3: Input: s = "aabb" Output: -...
Given two sorted integer arrays A and B, merge B into A as one sorted array. Note: You may assume that A has enough space to hold additional elements from B. The number of elements initialized in A and B aremandnrespectively. 归并排序 1 class Solution { 2 public: 3 void merge(int ...
如果1,2合并,再依次和3, 4...合并, 时间负责度就不一样了, 因为这样链表1和其他每个链表都比较1次 # Definition for singly-linked list.# class ListNode:# def __init__(self, x):# self.val = x# self.next = NoneimportheapqclassSolution:defmergeKLists(self,lists:List[ListNode])->ListNode:...
leetcode-23-Merge k Sorted Lists First, we can use priority_queue to deal with that, the time complexity is O(Nlog^k). Since priority_queue is basically a heap, every time we only need to compare the value in O(logk) time, instead of O(n) time. So we need to compare O(Nlog^...
用一个大小为K的最小堆(用优先队列+自定义降序实现)(优先队列就是大顶堆,队头元素最大,自定义为降序后,就变成小顶堆,队头元素最小),先把K个链表的头结点放入堆中,每次取堆顶元素,然后将堆顶元素所在链表的下一个结点加入堆中。 代码语言:javascript ...
{ k -= newIndex1 - index1 + 1; index1 = newIndex1 + 1; } else { k -= newIndex2 - index2 + 1; index2 = newIndex2 + 1; } } } double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) { int totalLength = nums1.size() + nums2.size(); if (totalLength %...
1213 Intersection of Three Sorted Arrays 80.0% Easy 1214 Two Sum BSTs 66.2% Medium 1215 Stepping Numbers 45.8% Medium 1216 Valid Palindrome III 50.1% Hard 1217 Minimum Cost to Move Chips to The Same Position Go 72.2% Easy 1218 Longest Arithmetic Subsequence of Given Difference 51.8% Med...
0004 Median of Two Sorted Arrays Go 26.60% Hard 0005 Longest Palindromic Substring 27.50% Medium 0006 ZigZag Conversion 32.20% Medium 0007 Reverse Integer Go 25.40% Easy 0008 String to Integer (atoi) 14.70% Medium 0009 Palindrome Number 43.70% Easy 0010 Regular Expression Matching 25.40%...
我们用 N 表示链表的总长度,考虑最坏情况,k 个链表的长度相等,都为 n 。 解法一 暴力破解 简单粗暴,遍历所有的链表,将数字存到一个数组里,然后用快速排序,最后再将排序好的数组存到一个链表里。 publicListNodemergeKLists(ListNode[]lists){List<Integer>l=newArrayList<Integer>();//存到数组for(ListNodeln...