Programming Fundamentals · Lesson 09

Introduction to C++

Meet C++, read your first complete program, and understand how source code becomes a running program.

Read the example

#include <iostream>

int main() {
    std::cout << "Hello, PAMS!" << '\n';
    return 0;
}

Hello, PAMS!

#include <iostream> makes the standard input/output declarations available. Our console program begins executing at main(). The braces { and } enclose its body.

std::cout sends output to the console. The << operators insert the message and then a newline character, '\n'. Double quotes surround a string; single quotes surround a character. The std:: prefix names the standard-library namespace.

The semicolon ends each statement in this example. return 0; reports successful completion. C++ distinguishes uppercase and lowercase letters: main and Main are different names.

A compile error prevents this program from building, such as a missing semicolon. A logic error can produce a running program with the wrong result. After editing the source, rebuild it to run the new version.

#include <iostream>

int main() {
    std::cout << "I am learning C++." << '\n';
    std::cout << "My first step with PAMS." << '\n';
    return 0;
}