#include <iostream>
#include <fstream>
using namespace std;
ifstream f("reguli.in");
ofstream g("reguli.out");

long long i,j,n,k,a[500010];

int main()
{
f>>n;
for (i=1;i<=n;i++)
{
    f>>a[i];
}
n--;
for (i=1;i<=n;i++)
{
    a[i]=a[i+1]-a[i];
}
i=2;
while (a[i]!=a[1] && i<n)
    i++;

if (i==n)
{
    g<<n<<"\n";
    for (i=1;i<=n;i++) g<<a[i]<<"\n";
}
else
{
    k=i-1;
  //  cout<<k;
    j=0;
    for (i=k+1;i<=n;i++)
    {
        j++;
        if (j==k+1) j=1;
        if (a[i]!=a[j]) {k=i;j=0;}
    }
    g<<k<<"\n";
    for (i=1;i<=k;i++) g<<a[i]<<"\n";
}

    return 0;
}