This file explains essential concepts for performing input and output operations in C++ programs using the header.
- Header: This header file provides functionalities for input/output (I/O) operations.
Standard Streams:
std::cout: An object of the ostream class used for sending formatted output to the console (typically). std::cin: An object of the istream class used for reading formatted input from the console (typically). std::cerr and std::clog: Objects of the ostream class used for printing error messages. std::cerr is unbuffered, while std::clog might be buffered.
- Stream Insertion Operator (<<): Used to send data to output streams. Manipulators: Functions that modify the behavior of streams for formatting output (e.g., std::endl, std::setw, std::fixed, std::setprecision).
#include <iostream>
int main() {
// Not recommended for large projects (potential naming conflicts)
using namespace std;
// Print to console
cout << "Hello, World!" << endl;
// Read an integer
int number;
cout << "Enter a number: ";
cin >> number;
// Print with formatting
cout << "You entered: " << setw(5) << number << endl;
return 0;
}
std::setw(width): Sets the minimum field width for output.
std::fixed and std::setprecision(precision): Controls formatting of floating-point numbers (fixed notation and number of decimal places).
Buffer Management
std::endl: Inserts a newline character and flushes the output buffer.
std::flush: Forces the output buffer to be flushed.
Reading Input
std::cin.ignore(): Discards characters from the input buffer (useful after reading numbers to avoid leftover characters).
std::getline(cin, string_variable): Reads a line of text from the console and stores it in a string variable.
Note: Consider error handling for robust input validation in practical applications.