#include <bits/stdc++.h>
using namespace std;
int n,k,l;  
bool a[15]; 
int main()
{
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        string j;
        cin>>j;          
        if(j=="purple") 
        {
            a[i]=1;
        }
        if(j=="blue") 
        {
            a[i]=1;
        }        
        if(j=="green")
        {
            a[i]=1;
        }  
        if(j=="orange") 
        {
            a[i]=1;
        }  
        if(j=="red") 
        {
            a[i]=1;
        }  
        if(j=="yellow") 
        {
            a[i]=1;
        }  
    }
    cout<<6-n<<endl; 
    if(a[1]=0) 
    {
        cout<<"purple";
    }
    if(a[2]=0) 
    {
        cout<<"blue";
    }        
    if(a[3]=0)
    {
        cout<<"green";
    }  
    if(a[4]=0) 
    {
        cout<<"orange";
    }  
    if(a[5]=0) 
    {
        cout<<"red";
    }  
    if(a[6]=0) 
    {
        cout<<"yellow";
    }  
    return 0;
}