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reference resources: https://blog.csdn.net/whereismatrix/article/details/104400205?spm=1001.2014.3001.5501 brief introduction In Eigen, there are Matrix and vector for linear algebra related operations, but it is also necessary to perform related operations on the coefficients in the Matrix, which is a normal functional requirement. The Arr ...

Some related to permutation: functions and stl containers 1. Sort (first address, last address, sorting mode cmp); cmp is user-defined, usually structured, and vector is packaged and taken away; 2.next_permutation starts from the second sequential full sort. If you want to print all, it is used in combination with the do while statement; 3. ...

1. Background Notes Daily use jsoncpp When creating a Json, it is often necessary to create a child json, assign a value to the child json, and then save it to the parent json. This code structure is inconsistent with human logic, making it difficult to write, read, and understand. 2. Optimized Discovery For the first few days cpp-http ...

Sequence table Sequence table commonly used are static sequence table and dynamic sequence table   Common dynamic sequence table   The code implements the sequence table, including the pushhead pushback poppead pop back of the sequence table, which can be combined with the previous address book:   Exercise remove the array of dup ...

Catalog abstract Emphasis of experiment Program Flowchart Database preparation Local SQL Server table building Remote MySQL Table Building Interface Development Login Dialog 1. Add icons to the dialog 2. Automatically focus to the first edit box when the form opens 3. Specific code implementation for login verification 4. Function ...

vectorvector<typename> namefunctionfunctionTime complexitypush_back(x)Add an element after the vectorO(1)pop_back()Delete the tail element of the vectorO(1)size()Get the number of elements of the vectorO(1)clear()Empty all elements in the vectorO(N), N is the number of vector elementsinsert(it,x)Insert an element x into any iterator it of ...

Fundamentals of C + + (V) C + + classes (Continued) Supplement to the previous section: When creating a class object, if the const keyword is added before the class name, the data in the created object cannot be modified. const Stock num3("abc", 123, 212); //A const object is created num3.show(); //report errors For const type class objec ...

C++ Virtual Functions and Polymorphisms Virtual Functions and Virtual Function Tables Normal functions do not affect class size Virtual function table: Because this pointer points to all virtual function header addresses to store memory segments, it is called a table What is a virtual function? A member function modified with virtual is call ...

1. Pointers and arrays The reason why pointers and arrays are basically equivalent is that pointers count and the internal processing of arrays in C + +. In many cases, you can use array names and pointer names in the same way. In most cases, C + + treats the array name as the address of the first element of the array. The value of pointer p i ...

A.Hello Xiaoming As the simplest check-in question, this question is adapted from hello world to investigate your string input and output ability. #include<bits/stdc++.h> using namespace std; int main(){ string s; cin>>s; cout<<"Hello "<<s<<endl; return 0; } B. Knowledgeable Xiao Ming Match ...