func leapYear(_ year: Int) { if year % 4 == 0 {     if year % 100 == 0 && year % 400 != 0 {         print("\(year) - Not a leap year!")     } else {         print("\(year) - Leap year!")         }     } else {         print("\(year) - Not a leap year!")     } } HI all! I apologise if question is simple (I'm a complete beginner in programming). I want to enter "leapYear(2021)" and I want to see that given year is leap year or not. I want to make this code short and the question is why if I remove last else I do not get output: "2021 - Not a leap year!"