var greeting = "Dzień dobry";
var displayGreeting;
 
function greets(person) {
    
    var fullName = person.name + " " + person.surname;
    

	 return function () { 
        console.log(greeting + " " + fullName);
    }
}
 
displayGreeting = greets({name: "Jan", surname: "Kowalski"});

displayGreeting();