Problem: This is an interactive task.

We have 2N balls arranged in a row, numbered 1, 2, 3, ..., 2N from left to right, where N is an odd number. Among them, there are N red balls and N blue balls.

While blindfolded, you are challenged to guess the color of every ball correctly, by asking at most 210 questions of the following form:

* You choose any N of the 2N balls and ask whether there are more red balls than blue balls or not among those N balls.



Now, let us begin.

Constraints

* 1 \leq N \leq 99
* N is an odd number.



* * *



Example

Input




Output

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define YES() printf("YES\n")
#define NO() printf("NO\n")
#define Yes() printf("Yes\n")
#define No() printf("No\n")
#define in(x,y,h,w) x >= 0 && x < h && y >= 0 && y < w

#define int long long
//using ll = long long;
using P = pair<int,int>;

template <typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template <typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
 
const int INF=1e+18;
const double EPS=1e-9;
const int MOD=1000000007;

const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};

bool ask(vector<int> &vec){
	cout << "?";
	for(int v : vec) cout << " " << v + 1;
	cout << endl;
	string s;
	cin >> s;
	return s == "Red";
}

signed main(){
	int n;
	cin >> n;
	string ans;
	for(int i = 0;i < n * 2;i++) ans += '?';
	vector<int> q;
	for(int i = 0;i < n;i++) q.push_back(i);
	bool isR = ask(q);
	int r = 0,b = n;
	if(!isR) swap(r,b);
	while(abs(r - b) > 1){
		int mid = (r + b) / 2;
		for(int i = 0;i < n;i++) q[i] = mid + i;
		if(ask(q)) r = mid;
		else b = mid;
	}
	if(r < b){
		ans[r] = 'R';
		ans[r + n] = 'B';
	}else{
		ans[b] = 'B';
		ans[b + n] = 'R';
	}
	int ma = max(b,r);
	for(int i = 0;i < n * 2;i++){
		q.clear();
		if(ma <= i && i < ma + n - 1){
			for(int j = -1;j < n;j++){
				if(ma + j != i) q.push_back(ma + j);
			}
			ans[i] = (ask(q) ? 'B' : 'R');
		}else{
			for(int j = 0;j < n - 1;j++){
				q.push_back(ma + j);
			}
			q.push_back(i);
			ans[i] = (ask(q) ? 'R' : 'B');
		}
	}
	cout << "! " << ans << endl;
}