原创 【leetcode】101. Symmetric Tree
Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary
2019-02-10 13:09:17
原创 【leetcode】40. Combination Sum II
Given a collection of candidate numbers (candidates) and a target number (target), find all unique combinations in cand
2019-02-10 13:09:17
原创 【leetcode】37. Sudoku Solver
Write a program to solve a Sudoku puzzle by filling the empty cells. A sudoku solution must satisfy all of the followin
2019-02-10 13:09:17
原创 【leetcode】445. Add Two Numbers II
You are given two non-empty linked lists representing two non-negative integers. The most significant digit comes first
2019-02-10 13:09:17
原创 【leetcode】216. Combination Sum III
Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used
2019-02-10 13:09:17
原创 【leetcode】203. Remove Linked List Elements
Remove all elements from a linked list of integers that have value val. Example: Input: 1->2->6->3->4->5->6, val = 6
2019-02-10 13:09:17
原创 【leetcode】547. Friend Circles
There are N students in a class. Some of them are friends, while some are not. Their friendship is transitive in nature
2019-02-09 01:28:57
原创 【leetcode】329. Longest Increasing Path in a Matrix
Given an integer matrix, find the length of the longest increasing path. From each cell, you can either move to four di
2019-02-09 01:28:57
3
原创 【leetcode】145. Binary Tree Postorder Traversal
Given a binary tree, return the postorder traversal of its nodes' values. Example: Input: [1,null,2,3] 1 \
2019-02-09 01:28:57
2
原创 【leetcode】617. Merge Two Binary Trees
Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are ov
2019-02-09 01:28:57
2
原创 【leetcode】2. Add Two Numbers
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order
2019-02-09 01:28:57
原创 【leetcode】215. Kth Largest Element in an Array
Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the
2019-02-09 01:28:57
1
原创 【leetcode】414. Third Maximum Number
Given a non-empty array of integers, return the third maximum number in this array. If it does not exist, return the ma
2019-02-09 01:28:57
2
原创 【leetcode】316. Remove Duplicate Letters
Given a string which contains only lowercase letters, remove duplicate letters so that every letter appear once and onl
2019-02-04 01:40:48
1
原创 【leetcode】111. Minimum Depth of Binary Tree
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the
2019-02-04 01:40:48
2