How to compile C++ in terminal

GCC compiler
- For Windows, you will need to install mingw
- For Linux, you will need to refer to your distributions package manager
- For Mac, you will need to use brew

First, let's make a simple C++ file named main.cpp

// main.cpp
#include <iostream>

int main()
{
  std::cout << "Hello World!\n";
}

Now, open your terminal in the same directory where the file was saved.
To compile the file
```
$ g++ main.cpp
```
You can replace main.cpp with the filename you chose. This will compile your file into an executable called a.out
Finally, to run the file
```
$ ./a.out
```
Incase you want to name the executable file
```
$ g++ main.cpp -o main
```
This will make the executable file as main

You've divided your main file into multiple files. Now what?

I created a new file called Universe.hpp in includes directory and main.cpp into src directory My directory now looks like

.
├── includes
│   └── Universe.hpp
└── src
    └── main.cpp

// Universe.hpp
#pragma once
#include <iostream>

class Universe
{
  public:
    Universe() {
      std::cout << "Hello Universe\n";
    }
};

and I changed my main.cpp to

// main.cpp
#include <iostream>
#include "Universe.hpp"

int main()
{
  std::cout << "Hello World!\n";

  Universe universe;
}

If I compile my main file now, I get an error

What this means is that gcc can't find my Universe.hpp file, we need to tell where the file is.

To tell gcc where are header files are located, we will use -I flag
```
$ g++ src/main.cpp -I includes
```
It compiles just fine with no errors and runs as well!

Compiling C++ Using Terminal