C++ Articles - Page 638 of 719

In this section, you will learn how to use SQLite in C/C++ programs.InstallationBefore you start using SQLite in our C/C++ programs, you need to make sure that you have SQLite library set up on the machine. You can check SQLite Installation chapter to understand the installation process.C/C++ Interface APIsFollowing are important C/C++ SQLite interface routines, which can suffice your requirement to work with SQLite database from your C/C++ program. If you are looking for a more sophisticated application, then you can look into SQLite official documentation.Serial NoAPI & Description1sqlite3_open(const char *filename, sqlite3 **ppDb)This routine opens a connection to an SQLite ... Read More

Virtual functions calling from a constructor or destructor is dangerous and should be avoided whenever possible as the virtual function we call is called from the Base class and not from the derived class.The reason is that in C++ Super-classes are constructed before derived classes. So, in the following example, as B must be instantiated, before D is instantiated. When B's constructor is called, it's not D yet, so the virtual function table still has the entry for B's copy of s().Example Code Live Demo#include using namespace std; class B {    public: B() {       s();    } ... Read More

In this section, you will learn how to use SQLite in C/C++ programs.InstallationBefore you start using SQLite in our C/C++ programs, you need to make sure that you have SQLite library set up on the machine. You can check the SQLite Installation chapter to understand the installation process.C/C++ Interface APIsFollowing are important C/C++ SQLite interface routines, which can suffice your requirement to work with SQLite database from your C/C++ program. If you are looking for a more sophisticated application, then you can look into SQLite official documentation.Serial NoAPI & Description1sqlite3_open(const char *filename, sqlite3 **ppDb)This routine opens a connection to an ... Read More

In C++, virtual and pure virtual functions are key features supporting polymorphism both allow different classes to respond uniquely to the same function call. What is Virtual Function A virtual function in C++ is a member function in a base class, which allows a function to be overridden in the derived class. This process helps in enabling runtime polymorphism. A virtual function is declared in the base class using the virtual keyword. Syntax Following is the syntax of the virtual function: class BaseClassName { public: virtual void func_name() { // implementation ... Read More

A pure virtual function is a function that has no implementation in the base class and must be overridden by any derived class. It is declared using = 0 in the base class. Pure Virtual Destructor When we want the base class to be abstract then we declare a pure virtual Destructor. A pure virtual Destructor can be declared in C++ after a destructor has been created as a pure virtual object. One of the most important things is that if a class contains a pure virtual destructor, it must provide a function body for the pure virtual destructor. ... Read More

What is an Assertions in C/C++? An assertion is a statement used to test assumptions made by the program. When an assertion fails, the program displays an error and stops. This is mainly used for debugging. In C and C++, assertions are handled using the assert() macro defined in the (C) or (C++) header file. Following is the declaration for assert() Macro. #include // in C // or #include in C++ assert(expression); The parameter of this assert() is expression: This can be a variable or any C/C++ expression. If ... Read More

In this section we will see how to execute the if and else section simultaneously in a C or C++ code. This solution is little bit tricky.When the if and else are executed one after another then it is like executing statements where if-else are not present. But here we will see if they are present how to execute them one after another.Example Code#include using namespace std; int main() {    int x = 10;    if(x > 5)   {       lebel_1: cout

In this article, we will demonstrate how to implement an AVL tree. An AVL tree is a self-balancing binary search tree in which the height difference between the left and right subtrees (balance factor) of any node cannot exceed one. AVL TREE Following are the points of an AVL tree − Tree rotation is a way to change the structure of an AVL tree without changing the order of the elements. It helps keep the tree balanced by moving one node up and one node down. Tree rotations are mainly used ... Read More

In this section we will see what are the differences between *ptr++, *++ptr and ++*ptr in C++.Here we will see the precedence of postfix++ and prefix++ in C or C++. The precedence of prefix ++ or -- has higher priority than dereference operator ‘*’ and postfix ++ or -- has priority higher than both prefix ++ and dereference operator ‘*’.When ptr is a pointer, then *ptr++ indicates *(ptr++) and ++*prt refers ++(*ptr)Example Code Live Demo#include using namespace std; int main() { char arr[] = "Hello World"; char *ptr = arr; ++*ptr; cout

A hash table is a data structure which is used to store key-value pairs. Hash function is used by hash table to compute an index into an array in which an element will be inserted or searched.Linear probing is a collision resolving technique in Open Addressed Hash tables. In this method, each cell of a hash table stores a single key–value pair. If a collision is occurred by mapping a new key to a cell of the hash table that is already occupied by another key. This method searches the table for the following closest free location and inserts the ... Read More