C++ cout, cin, endl

The C++ cout, cin, and endl are commonly used objects and manipulators for input and output operations.

1. cout:

• cout is an instance of the ostream class, which is used for sending output to the standard output stream (usually the console or terminal).
• You can use cout to display text and data on the screen.
• Example:

 #include <iostream>

 int main() {
     std::cout << "Hello, world!" << std::endl;
     return 0;
 }

In this example, “Hello, world!” is displayed on the console.

2. cin:

• cin is an instance of the istream class, which is used for reading input from the standard input stream (usually the keyboard).
• You can use cin to receive input from the user.
• Example:

 #include <iostream>

 int main() {
     int num;
     std::cout << "Enter a number: ";
     std::cin >> num;
     std::cout << "You entered: " << num << std::endl;
     return 0;
 }

In this example, the user is prompted to enter a number, which is then stored in the variable num.

3. endl:

• endl is a manipulator that represents the end of a line or newline character ('\n').
• When used with cout, it not only outputs a newline character but also flushes the output buffer, ensuring that the text is displayed immediately.
• Example:

 #include <iostream>

 int main() {
     std::cout << "Line 1" << std::endl;
     std::cout << "Line 2" << std::endl;
     return 0;
 }

In this example, “Line 1” and “Line 2” are displayed on separate lines due to the use of endl.

While cout and cin are standard objects provided by the C++ Standard Library for input and output, endl is a standard manipulator. These three components are commonly used when working with console-based input and output operations in C++.