#include <iostream>
#include <algorithm>
#include <cstdio>
#include <string>

#define ll long long

using namespace std;

int main(){

   int d;
   cin>>d;

   int tmp;
   int f=0,s=0;
   int a[10001];
   for(int i=0;i<=d;++i) cin>>a[i];
   if(d<3){
      cout<<d<<endl;
      for(int i=0;i<=d;++i){
          cout<<a[i];
          if(i==d) cout<<endl;
          else cout<<" ";
      }
      return 0;
   }
   for(int i=d;i>=3;--i){
     a[i-2]+=a[i];
     a[i]=0;
   }

   int dem=2;
   /*ここにdemの処理*/
   if(!a[1]) dem=0;
   else if(!a[2]) dem=1;

   cout<<dem<<endl; //次数 
   cout<<a[0];  //定数項
   if(dem>=1) cout<<" "<<a[1];
   if(dem>=2) cout<<" "<<a[2];
   cout<<endl;
   return 0;
}