The iostream is the head er file which contains all the functions of program like cout, cin and etc.
#include <iostream>
int main() {
// Display text on the console
std::cout << "Hello, World!" << std::endl;
// Receive input from the user
int userInput;
std::cout << "Enter a number: ";
std::cin >> userInput;
// Display the entered number
std::cout << "You entered: " << userInput << std::endl;
return 0;
}