using namespace std;
#include<fstream>
#include<stdio.h>
#define nmax 500005

long long a[nmax];
int n;

int main()
{
FILE *fin=fopen("reguli.in","r"),
     *fout=fopen("reguli.out","w");
     
int i;
fscanf(fin,"%d",&n);
for(i=1;i<=n;i++) fscanf(fin,"%lld",&a[i]);
for(i=1;i<n;i++) a[i]=a[i+1]-a[i];
n--;

int li,lf,m,nr,ok,temp,j;
li=1,lf=n;

ok=0;
for(m=1;!ok;m++)
{  
  ok=1;
  for(i=m+1,j=1;i<=n&&ok;i++,j=(j==m?1:j+1))
       if(a[i]!=a[j])
          ok=0;
}
 
li=m-1; 
fprintf(fout,"%d\n",li);
for(i=1;i<=li;i++)
   fprintf(fout,"%lld\n",a[i]);
   
fclose(fin);
fclose(fout);
return 0;   
}