## Luogu P3327 [SDOI2015] sum of approximate numbers

Title Description
Let d(x) be the divisor of X, and given N and M, find \ sum ^ N {I = 1} \ sum ^ M {J = 1} d(ij) ∑ i=1N ∑ j=1M d(ij)
I / O format
Input format:
The input file contains multiple sets of test data. The first line, an integer T, represents the number of groups of test data. Next t lines, two integers N and M for eac ...

Posted on *Fri, 03 Apr 2020 17:54:01 -0700* by **mustng66**

## C + + implementation of direct insertion algorithm

Direct insertion algorithm: insert a keyword to be sorted into the proper position of the ordered sequence according to the size of its value each time until all the keywords to be sorted are inserted into the ordered sequence.
Theoretically, in the direct insertion sort, the second loop can end ahead of time, that is, an element does not cycle ...

Posted on *Fri, 03 Apr 2020 16:56:23 -0700* by **Beavis2084**

## Shelcode writing framework in Window s (introductory)

Shellcode
Definition
Is an injectable instruction (opcode) that can be run within an attacked program.
Characteristic
The shellcode operates directly on registers and functions, so the opcode must be in 16-bit form.Therefore, shellcodes cannot be written in high-level languages.Run in memory, not on a fixed host process.
Utilization princi ...

Posted on *Thu, 02 Apr 2020 10:27:00 -0700* by **suma237**

## [HDU 2066] a person's journey

Problem Description
Although Caoer is a road crazy (i.e. he has been in Hangzhou Electric Power for more than a year, and even lost his way in the campus, Khan ~), Caoer still likes to travel, because he will meet many people (prince charming, ^ 0 ^), many things, rich experience and beautiful scenery during the journey Cao'er wants to go to ma ...

Posted on *Thu, 02 Apr 2020 04:36:32 -0700* by **pkSML**

## C + + overloaded constructors cannot call each other

The overloaded constructors in java classes can call each other, as follows:
1 public class TestConstructor {
2 private int value;
3
4 public TestConstructor(int value) {
5 this.value = value;
6 System.out.println("constructor1:"+this);
7 }
8
9 public TestConstructor() {
10 this(10);
11 ...

Posted on *Wed, 01 Apr 2020 03:29:10 -0700* by **bluebutterflyofyourmind**

## 6, C + + inverse discrete Fourier transform

C + + inverse discrete Fourier transform
1, Preface:
This course takes on the above discrete Fourier transform and is used for inverse discrete Fourier transform.
2, Design objectives
The complex array is transformed by inverse discrete Fourier transform, and the available image classes are generated.
3, Detailed steps
Input: complex array ...

Posted on *Tue, 31 Mar 2020 18:35:05 -0700* by **christa**

## BZOJ1857: [Scoi2010] conveyor belt (three sets and three branches)

Time Limit: 1 Sec Memory Limit: 64 MBSubmit: 2005 Solved: 1091[Submit][Status][Discuss]
Description
There are two conveyor belts on A 2D plane, each belt can be regarded as A line segment. The two belts are line AB and line CD. The moving speed of lxhgww is P on AB, Q on CD and R on plane. Now lxhgww wants to go from point A to point D, and ...

Posted on *Mon, 23 Mar 2020 08:10:40 -0700* by **kevinkorb**

## Static member of C + + -- a detailed discussion on static decorated member

First of all, we understand it literally
Member: member variable, member function.
static modifies member variables, as well as member functions.
Static is declared static and is called a static member. No matter how many objects this class creates, there is only one copy of static members, which is shared by all objects belonging to this class ...

Posted on *Thu, 19 Mar 2020 08:34:52 -0700* by **rar_ind**

## Analysis of HAL Method Call Flow in OpenCV

There are some so-called HAL(Hardware Acceleration Layer) implementations in OpenCV that seem to be hardware related by name, but they are not. It can be understood that a faster version of OCV implementation is better.What this article does is to find out its implementation or cut into the process to get through the whole function call logic.T ...

Posted on *Wed, 18 Mar 2020 11:00:02 -0700* by **readourlines**

## Draw a polygon using QT

Catalog
1. overview
2. implementation
2.1. code
2.2. analysis
3. results
1. overview
You can draw polygons through QT redraw events and mouse events. The easiest way is to rewrite event handling functions such as paintEvent and mousePressEvent in the form that inherits QWidget. QT ...

Posted on *Thu, 05 Mar 2020 23:51:47 -0800* by **woody79**