package ru.alexandr;

public class Calculate {
    public String echo(String value){
	    return String.format("%s %s %s", value, value, value);
    }
    public static void main(String[] args) {
	    Calculate calc = new Calculate();
	    System.out.println(calc.echo("ahh"));
    }	
}
package ru.alexandr;

public class Calculate {
    public static void main(String[] args){
	System.out.println("Hello world!");
    }
}
add structure