fn main() {
    println!fn main() {
                println!("Hello, world!");
            }
(fn main() {
     fn mafn main() {
             fn main() {
                 println!("Hello, world!");
             }
 println!("Hello, world!");
          }
in() {fn main() {
          println!("Hello, world!");
      }

         println!("Hello, world!");
     }
            println!("Hello, world!");
             }
"Hello, world!");
}
