原创 Leetcode: Construct Binary Tree from Inorder and Postorder Traversal
Given inorder and postorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do n
2020-07-05 14:55:48
原创 Leetcode: Gas Station
There are N gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car with
2020-07-05 14:55:38
原创 Leetcode: Length of Last Word
Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last wo
2020-02-20 15:58:12
原创 Leetcode: Word Break
Given a string s and a dictionary of words dict, determine if s can be segmented into a space-separated sequence of o
2020-02-20 15:58:12
原创 Leetcode: Valid Sudoku
Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules. The Sudoku board could be partially filled,
2020-02-20 15:58:12
原创 Leetcode: Word Search
Given a 2D board and a word, find if the word exists in the grid. The word can be constructed from letters of sequen
2020-02-20 15:58:12
原创 Leetcode: Validate Binary Search Tree
Given a binary tree, determine if it is a valid binary search tree (BST). Assume a BST is defined as follows: The le
2020-02-20 15:58:12
原创 Leetcode: Combinations
Given two integers n and k, return all possible combinations of k numbers out of 1 ... n. For example, If n = 4 and
2020-02-20 15:58:12
原创 Leetcode: Convert Sorted List to Binary Search Tree
Given a singly linked list where elements are sorted in ascending order, convert it to a height balanced BST. Similar m
2020-02-20 15:58:02
原创 Leetcode: ZigZag Conversion
The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to dis
2020-02-20 15:58:01
原创 Leetcode: Binary Tree Zigzag Level Order Traversal
Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then righ
2020-02-20 15:58:01
原创 Leetcode: Insertion Sort List
Sort a linked list using insertion sort. /** * Definition for singly-linked list. * public class ListNode { * in
2020-02-20 15:58:01
原创 Leetcode: Restore IP Addresses
Given a string containing only digits, restore it by returning all possible valid IP address combinations. For exampl
2020-02-20 15:58:00
原创 Leetcode: Sum Root to Leaf Numbers
Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is
2020-02-20 15:58:00
原创 Leetcode: Construct Binary Tree from Preorder and Inorder Traversal
Given preorder and inorder traversal of a tree, construct the binary tree. Note: You may assume that duplicates do no
2020-02-20 15:58:00