Puxuan's Blog

题目Longest Substring Without Repeating Characters Given a string s, find the length of the longest substring without duplicate characters. Example 1:Input: s = “abcabcbb”Output: 3Explanation: The answer is “abc”, with the length of 3. Example 2:Input: s = “bbbbb”Output: 1Explanation: The answer is “b”, with the length of 1. Example 3:Input: s = “pwwkew”Output: 3Explanation: The answer is “wke”, with the length of 3.Notice that the answer must be a substring, “pwke” is a subseque...

Complete code can be foound here: (https://github.com/Interstellarss/mystl/tree/main/include/ptr) Smart PointerSmart pointers are a type of pointer that automatically manage the memory of the object they point to. They are used to prevent memory leaks and other memory-related errors. There are three types of smart pointers: std::unique_ptr std::shared_ptr std::weak_ptr unique_ptrunique_ptr is a smart pointer that owns and manages another object through a pointer and disposes of that object ...

题目描述Word Ladder [HARD] A transformation sequence from word beginWord to word endWord using a dictionary wordList is a sequence of words beginWord -> s1 -> s2 -> … -> sk such that: Every adjacent pair of words differs by a single letter. Every si for 1 <= i <= k is in wordList. Note that beginWord does not need to be in wordList. sk == endWord Given two words, beginWord and endWord, and a dictionary wordList, return the number of words in the shortest tr...

题目描述Imbalanced Array[1900] You are given an array a consisting of n elements. The imbalance value of some subsegment of this array is the difference between the maximum and minimum element from this segment. The imbalance value of the array is the sum of imbalance values of all subsegments of this array. For example, the imbalance value of array [1, 4, 1] is 9, because there are 6 different subsegments of this array: [1] (from index 1 to index 1), imbalance value is 0; [1, 4] (from index 1 to...

HashTablehash table 实现： 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168#ifndef MY_HASH_TABLE#define MY_HASH_TABLE#include "my_allocator.h"...

my set: 1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253#ifndef MY_SET_H#define MY_SET_H#include "my_rbtree.h"#include "my_utility.h"namespace mystl{template <typename Key, typename Compare = std::less<Key>, typename Alloc = mystl::MyAllocator<mystl::RBTreeNode<Key>>>class MySet{private: using tree_type = mystl::MyRBTree<Key, Key, mystl::identity<Key>, Compare, Alloc>; tre...

题目描述[MEDIUM] You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security systems connected and it will automatically contact the police if two adjacent houses were broken into on the same night. Given an integer array nums representing the amount of money of each house, return the maximum amount of money you can rob tonight without alertin...

题目描述[MEDIUM] Given an integer array nums of unique elements, return all possible subsets (the power set). The solution set must not contain duplicate subsets. Return the solution in any order. Example 1: 12Input: nums = [1,2,3]Output: [[3],[1],[2],[1,2,3],[1,3],[2,3],[1,2],[[]] Example 2: 12Input: nums = [0]Output: [[0]] Constraints: 1 <= nums.length <= 10-10 <= nums[i] <= 10All the numbers of nums are unique. 思路We can use backtracking (DFS) to generate all p...

题目描述[Medium] Given an m x n grid of characters board and a string word, return true if word exists in the grid. The word can be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring. The same letter cell may not be used more than once. Example 1: 12Input: board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","...

题目描述[MEDIUM] Given two integers n and k, return all possible combinations of k numbers chosen from the range [1, n]. You may return the answer in any order. Example 1: 1234Input: n = 4, k = 2Output: [[2,4],[3,4],[2,3],[1,2],[1,3],[1,4]]Explanation: There are 4 choose 2 = 6 total combinations.Note that combinations are unordered, i.e., [1,2] and [2,1] are considered to be the same combination. Example 2: 123Input: n = 1, k = 1Output: [[1]]Explanation: There is 1 choose 1 = 1 total combination...