Hello, world!

Test post

Hello, world.

class Hello {
    public Hello(string message) {
        Console.WriteLine("Hello, " + message);
    }

    static void Main(string[] args) {
        new Hello("world");
    }
}

About this, it is this.

Also, if $a+b=c$, then

\[a^2 + 2ab + b^2 = c^2\]