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原创 Leetcode - 429 - N-ary Tree Level Order Traversal

Recursive:Java:private List<List<Integer>> dfs(Node node, List<List<Integer>> res, int level) { if (node == null) return res; if (res.size() == level) res.add(new ArrayList<>()); res.get(level).a..

2021-02-09 11:42:35 186

原创 Leetcode - 589 - N-ary Tree Preorder Traversal

Recursive:Java:class Solution { public List<Integer> list = new ArrayList<>(); public List<Integer> preorder(Node root) { if (root == null) return list; list.add(root.val); for(N..

2021-02-09 11:30:46 233

原创 Leetcode - 590 - N-ary Tree Postorder Traversal (easy)

Recursive:Java:class Solution { List<Integer> list = new ArrayList<>(); public List<Integer> postorder(Node root) { if (root == null) return list; for(Node node: root.children) ..

2021-02-09 11:18:24 177

原创 Leetcode - 144 - Binary Tree Preorder Traversal (medium)

Recursive:Java:public List<Integer> preorderTraversal(TreeNode root) { List<Integer> pre = new LinkedList<Integer>(); preHelper(root,pre); return pre;}public void preHelper(TreeNode root, List<Integer> pre) { if(root==nul

2021-02-09 11:06:38 146

原创 Leetcode - 94 - Binary Tree Inorder Traversal (medium)

Iterativeright child doesn't exist: save all the children on the left chain does exist: save the top of the stack in the resultPython:def inorderTraversal(self, root): res, stack = [], [] while (root or stack...

2021-02-09 10:57:02 143 1

原创 mmdetection 修改config训练自己的detector

简单来说，首页open-mmlab/mmdetection: OpenMMLab Detection Toolbox and Benchmark (github.com)Supported methods模块点连接，如faster rcnn进入后选择模型，config为config 文件所在地址，复制到自己的config路径后修改，如./configs/fire下载model放置./checkpoints找到上级文件，按照格式覆盖上级所含的参数常用的需要改的参数为：num

2021-01-14 10:41:34 974 2

原创 darknet- yolov4 常用命令

AlexeyAB/darknet: YOLOv4v / Scaled-YOLOv4 - Neural Networks for Object Detection (Windows and Linux version of Darknet ) (github.com)To check accuracy mAP@IoU=50:darknet.exe detector map data/obj.data yolo-obj.cfg backup\yolo-obj_7000.weights To che..

2021-01-14 10:10:05 810

原创 mmdetection常用命令

1. Testpython tools/test.py configs/ballon/mask_rcnn_r50_caffe_fpn_mstrain-poly_1x_balloon.py work_dirs/mask_rcnn_r50_caffe_fpn_mstrain-poly_1x_balloon.py/latest.pth --eval bbox segm2. Trainpython tools/train.py configs/ballon/mask_rcnn_r50_caffe_f

2021-01-04 13:42:15 2298 1

原创 Leetcode - 49 - Group Anagrams (medium)

Given an array of stringsstrs, groupthe anagramstogether. You can return the answer inany order.AnAnagramis a word or phrase formed by rearranging the letters of a different word or phrase, typically using all the original letters exactly once....

2020-12-19 23:28:56 145 2

原创 Leetcode - 242 - Valid Anagram (easy)

Solutions:(1) Arrays.sort(str) directlyJava:public boolean isAnagram(String s, String t) { if (s.length() != t.length()) { return false; } char[] str1 = s.toCharArray(); char[] str2 = t.toCharArray(); Arrays.sort(str1);..

2020-12-19 23:09:48 180 1

原创 Leetcode - 239 - Sliding Window Maximum (hard)

You are given an array of integersnums, there is a sliding window of sizekwhich is moving from the very left of the array to the very right. You can only see theknumbers in the window. Each time the sliding window moves right by one position.Return...

2020-12-19 18:18:36 129 1

原创 Leetcode - 155 - Min Stack (easy)

Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the top element. getMin() -- Retrieve the minimum ele

2020-12-19 16:22:06 189 1

原创 Leetcode - 20 - Valid Parentheses (easy)

Given a stringscontaining just the characters'(',')','{','}','['and']', determine if the input string is valid.An input string is valid if:Open brackets must be closed by the same type of brackets. Open brackets must be closed in the correct ...

2020-12-17 19:36:46 208 2

原创 Leetcode - 42 - Trapping Rain Water (hard)

Givennnon-negative integers representing an elevation map where the width of each bar is1, compute how much water it can trap after raining.Solutions:ans = sum {min⁡(left_max,right_max)−height[i]min(left_max,right_max)−height[i] for all element...

2020-12-10 10:15:45 146

原创 Leetcode - 641 - Design Circular Deque (medium)

Solutions:C++:#include <vector>#include <iostream>using namespace std;class MyCircularDeque {private: vector<int> buffer; int cnt; int k; int front; int rear;public: /** Initialize your data structure..

2020-12-10 00:21:16 98

原创 Leetcode - 66 - Plus One (easy)

Given anon-emptyarray of decimal digitsrepresenting a non-negative integer, incrementone to the integer.The digits are stored such that the most significant digit is at the head of the list, and each element in the array contains a single digit.You...

2020-12-09 08:00:45 102

原创 Leetcode - 88 - Merge Sorted Array (easy)

Given two sorted integer arraysnums1andnums2, mergenums2intonums1as one sorted array.Note:The number of elements initialized innums1andnums2aremandnrespectively. You may assume thatnums1has enough space (size that isequaltom+n) t...

2020-12-08 20:54:26 122

原创 Leetcode - 84 - Largest Rectangle in Histogram (hard)

Givennnon-negative integers representing the histogram's bar height where the width of each bar is 1, find the area of largest rectangle in the histogram.

2020-12-02 00:41:53 115 2

原创 Leetcode - 21 - Merge Two Sorted Lists (easy)

Merge two sorted linked lists and return it as a newsortedlist. The new list should be made by splicing together the nodes of the first two lists.Solutions:(1) Recursive:The recursive function mergeTwoLists(ListNode l1, ListNode l2) mean merge...

2020-12-01 15:15:08 162

原创 Leetcode - 189 - Rotate Array (medium)

Given an array, rotate the array to the right byksteps, wherekis non-negative.Follow up:Try to come up as many solutions as you can, there are at least 3 different ways to solve this problem. Could you do it in-place with O(1) extra space?So...

2020-12-01 13:39:55 144

原创 Leetcode - 25 - Reverse Nodes in k-Group (hard)

Given a linked list, reverse the nodes of a linked listkat a time and return its modified list.kis a positive integer and is less than or equal to the length of the linked list. If the number of nodes is not a multiple ofkthen left-out nodes, in the...

2020-11-29 00:20:42 292

原创 Leetcode - 26 - Remove Duplicates from Sorted Array

Given a sorted arraynums, remove the duplicatesin-placesuch that each element appears onlyonceand returns the new length.Do not allocate extra space for another array, you must do this bymodifying the input arrayin-placewith O(1) extra memory.C...

2020-11-28 21:12:49 83

原创 Leetcode - 142 - Linked List Cycle II

Given a linked list, return the node where the cycle begins. If there is no cycle, returnnull.There is a cycle in a linked list if there is some node in the list that can be reached again by continuously following thenextpointer. Internally,posis us...

2020-11-27 14:31:36 121

原创 Leetcode - 141 - Linked List Cycle

Givenhead, the head of a linked list, determine if the linked list has a cycle in it.There is a cycle in a linked list if there is some node in the list that can be reached again by continuously following thenextpointer. Internally,posis used to den...

2020-11-27 13:37:26 149

原创 Leetcode - 24 - Swap Nodes in Pairs

Given alinked list, swap every two adjacent nodes and return its head.You maynotmodify the values in the list's nodes. Only nodes itself may be changed.Solutions:(1) Recursive: when head.next.next pairs are swapped, only need to swap the first t...

2020-11-25 14:10:19 115 1

原创 Leetcode - 206 - Reverse Linked List

Reverse a singly linked list.Example:Follow up:A linked list can be reversed either iteratively or recursively. Could you implement both?Solutions:(1) IterativeWe want the curr->next to be prev and in order to iterate in the loop, three.

2020-11-24 14:01:47 109

原创 Leetcode - 70 - Climbing Stairs

You are climbing a staircase. It takes n steps to reach the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?Solutions:(1) Appliesto a small nTry to compose the big abstract problem by simila..

2020-11-23 23:49:29 153

原创 Leetcode - 11 - Container With Most Water

Given n non-negative integers a1, a2, ..., an, where each represents a point at coordinate (i, ai). n vertical lines are drawn such that the two endpoints of the line i is at (i, ai) and (i, 0). Find two lines, which, together with the x-axis forms a cont.

2020-11-23 15:06:05 101

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