/*author: hyperion_1724
  date: 
*/

//Optional FAST

//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,fma,abm,mmx,avx,avx2,tune=native")

//Required Libraries

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/detail/standard_policies.hpp>

//Required namespaces

using namespace std;
using namespace __gnu_pbds;

//Required defines

//#define endl '\n'

#define READ(X) cin>>X;
#define READV(X) long long X; cin>>X;
#define READAR(A,N) long long A[N]; for(long long i=0;i<N;i++) {cin>>A[i];}
#define rz(A,N) A.resize(N);
#define sz(X) (long long)(X.size())
#define pb push_back
#define pf push_front
#define fi first
#define se second
#define trav(x,A) for(auto &x:A)
#define FORI(a,b,c) for(long long a=b;a<c;a++)
#define FORD(a,b,c) for(long long a=b;a>c;a--)

//Required typedefs

typedef tree<long long,null_type,less<long long>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef tree<long long,null_type,greater<long long>,rb_tree_tag,tree_order_statistics_node_update> ordered_set1;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<long long,long long> pll;
typedef vector<int> veci;
typedef vector<long long> vecl;

//Required Constants

const long long inf=(long long)1e18;
const long long MOD=(long long)(1e9+7);
const long long INIT=(long long)(1e6+1);

//Required Functions

ll power(ll x,ll y) 
{ 
    if (y == 0) 
        return 1; 
    ll p = power(x, y/2) % MOD; 
    p = (p * p) % MOD; 
  
    return (y%2 == 0)? p : (x * p) % MOD; 
}
ll modInverse(ll a) 
{ 
   return power(a,MOD-2); 
   
}

//Work

int main()
{
    
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    READV(N);
    char A[2*N]={0};
    cout<<"? ";
    FORI(i,1,N+1)
    {
        cout<<i<<" ";
    }
    cout<<endl;
    string S;
    READ(S);
    if (S=="Red")
    {
        ll lo=2,hi=N+1;
        while (lo<hi)
        {
            ll mid=(lo+hi)/2;
            cout<<"? ";
            FORI(i,mid,mid+N)
            {
                cout<<i<<" ";
            }
            cout<<endl;
            string Z;
            READ(Z);
            if (Z=="Red")
            {
                lo=mid+1;
            }
            else
            {
                hi=mid;
            }            
        }
        A[lo-2]='R';
        A[lo+N-2]='B';
        FORI(i,1,2*N+1)
        {
            if (i<lo-1 || i>lo+N-1)
            {
                cout<<"? "<<i<<" ";
                FORI(j,lo,lo+N-1)
                {
                    cout<<j<<" ";
                }
                cout<<endl;
                string Z;
                READ(Z);
                if(Z=="Red")
                {
                    A[i-1]='R';
                }
                else
                {
                    A[i-1]='B';
                }
            }
            else if(lo-1<i && i<lo+N-1)
            {
                cout<<"? "<<i<<" ";
                FORI(j,1,2*N+1)
                {
                    if (j<lo-1 || j>lo+N-1)
                    {
                        cout<<j<<" ";
                    }
                }
                cout<<endl;
                string Z;
                READ(Z);
                if(Z=="Red")
                {
                    A[i-1]='R';
                }
                else
                {
                    A[i-1]='B';
                }
                
            }
        }
    }
    else
    {
        ll lo=2,hi=N+1;
        while (lo<hi)
        {
            ll mid=(lo+hi)/2;
            cout<<"? ";
            FORI(i,mid,mid+N)
            {
                cout<<i<<" ";
            }
            cout<<endl;
            string Z;
            READ(Z);
            if (Z=="Blue")
            {
                lo=mid+1;
            }
            else
            {
                hi=mid;
            }            
        }
        A[lo-2]='B';
        A[lo+N-2]='R';
        FORI(i,1,2*N+1)
        {
            if (i<lo-1 || i>lo+N-1)
            {
                cout<<"? "<<i<<" ";
                FORI(j,lo,lo+N-1)
                {
                    cout<<j<<" ";
                }
                cout<<endl;
                string Z;
                READ(Z);
                if(Z=="Red")
                {
                    A[i-1]='R';
                }
                else
                {
                    A[i-1]='B';
                }
            }
            else if(lo-1<i && i<lo+N-1)
            {
                cout<<"? "<<i<<" ";
                FORI(j,1,2*N+1)
                {
                    if (j<lo-1 || j>lo+N-1)
                    {
                        cout<<j<<" ";
                    }
                }
                cout<<endl;
                string Z;
                READ(Z);
                if(Z=="Red")
                {
                    A[i-1]='R';
                }
                else
                {
                    A[i-1]='B';
                }
                
            }
        }
    }
    cout<<"! ";
    FORI(i,0,2*N)
    {
        cout<<A[i];
    }
    cout<<endl;
    
    

    return 0;
}

Measured memory_bytes: 724