import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;

public class No40 {

	public static void main(String[] args) throws IOException{
		//多項式の割り算
		String[] str = readStr();
		int D = Integer.parseInt(str[0]);
		int[] a = new int[D + 1];
		
		for(int i = 0;i <= D;i++) {
			a[D - i] = Integer.parseInt(str[1].split(" ")[i]);
		}
		
		for(int i = 0;i < D - 2;i++) {
			a[i + 2] += a[i];
			a[i] = 0;
		}
		
		int Dd = 0;
		for(int i = Math.max(0, D - 2);i <= D ;i++) {
			if(a[i] > 0) {
				Dd = D - i;
				break;
			}
			
		}
		
		System.out.println(Dd);
		for(int i = D;i >= D - Dd;i--) {
			System.out.print(a[i]);
			if(i == D - Dd) {
				System.out.println();
			}else {
				System.out.print(" ");
			}
		}



	}

	public static String[] readStr() throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		ArrayList<String> list = new ArrayList<>();

		do {
			list.add(br.readLine());
		}while(br.ready());

		br.close();

		String[] text = new String[list.size()];
		list.toArray(text);

		return text;

	}
}