原创 【Leetcode】Combination sum 1，2
【題目】 【分析】 首先，先sort, 如果target > 0: 【代碼】 using recursive 這恐怕的 O(n2)... 過程： before recursion : [2] before recursion : [
2020-06-26 17:13:51
原创 【Leetcode】Lowest common treenode in binary tree
【題目】 Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree. According to the defi
2020-06-26 17:13:39
原创 【Leetcode】Search for a range
【題目】 Given a sorted array of integers, find the starting and ending position of a given target value. Your algorith
2020-06-26 17:13:39
原创 【Leetcode】Largest Number
【題目】 Given a list of non negative integers, arrange them such that they form the largest number. For example, given [
2020-06-26 17:13:39
原创 【Leetcode】Gas Station
【題目】 There are N gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car
2020-06-26 17:13:39
原创 【Eclipse】Eclipse快捷鍵總結
Eclipse中10個最有用的快捷鍵組合 一個Eclipse骨灰級開發者總結了他認爲最有用但又不太爲人所知的快捷鍵組合。通過這些組合可以更加容易的瀏覽源代碼，使得整體的開發效率和質量得到提升。 1. ctrl
2020-06-26 17:13:39
原创 【leetcode】Count Primes
【題目】 Description: Count the number of prime numbers less than a non-negative number, n. Credits: Special thanks to
2020-02-25 02:17:58
原创 【Leetcode】Sort List in O(nlogn) O(1)space
【題目】 【思路】 First of all, allow me to explain the meaning of strict O(1) auxiliary space complexity. It means the max
2020-02-25 02:17:58
原创 【Leetcode】Lowest Common Ancestor of a Binary Search Tree
【題目】 Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. Accordin
2020-02-25 02:17:58
原创 【Leetcode】Delete Node in a LinkedList
【題目】 Write a function to delete a node (except the tail) in a singly linked list, given only access to that node. Su
2020-02-25 02:17:58
原创 【Leetcode】Panlidrome Linked List
【題目】 Given a singly linked list, determine if it is a palindrome. Follow up: Could you do it in O(n) time and O(1) spa
2020-02-25 02:17:58
原创 【Leetcode】Rotate List
【題目】 Given a list, rotate the list to the right by k places, where k is non-negative. For example: Given 1->2->3->4->5
2020-02-25 02:17:58
原创 【Leetcode】Merge K Sorted Linked List
【題目】 Merge k sorted Linked Lists and return it as one sorted lists. Analyze and describe its complexity . 【思路】 leetcode
2020-02-25 02:17:58
原创 【Leetcode】Implement Queue using Stacks
【題目】 Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue.pop()
2020-02-25 02:17:58
原创 【Leetcode】Path sum 2
【題目】 Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For examp
2020-02-25 02:17:58