//1 1 2 3 5 8
//числа фибоначчи

public class lesson1712 {

	public static int fib(int n){
		if (n == 1 || n == 2) {
			return 1;
		}
		return (fib(n-1) + fib(n-2));
	}

	public static void main(String[] args){
		System.out.println(fib(6));


	}
}