#include <bits/stdc++.h>
using namespace std;
static inline void canhazfast() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
}
template <typename T>
T gcd(T a, T b) {
  return b ? gcd(b, a % b) : a;
}
template <typename T>
T extgcd(T a, T b, T &x, T &y) {
  T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
  while (b) {
    T q = a / b;
    a %= b;
    swap(a, b);
    x0 -= q * x1;
    swap(x0, x1);
    y0 -= q * y1;
    swap(y0, y1);
  }
  x = x0;
  y = y0;
  return a;
}
static inline int ctz(unsigned x) { return __builtin_ctz(x); }
static inline int ctzll(unsigned long long x) { return __builtin_ctzll(x); }
static inline int clz(unsigned x) { return __builtin_clz(x); }
static inline int clzll(unsigned long long x) { return __builtin_clzll(x); }
static inline int popcnt(unsigned x) { return __builtin_popcount(x); }
static inline int popcntll(unsigned long long x) {
  return __builtin_popcountll(x);
}
static inline int bsr(unsigned x) { return 31 ^ clz(x); }
static inline int bsrll(unsigned long long x) { return 63 ^ clzll(x); }
vector<int> adj[608];
vector<int> part[2];
vector<int> x, y, path;
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &s) {
  for (const T &x : s) os << x << ' ';
  return os;
}
void pri(const vector<int> &s, int b, int e) {
  for (int i = b; i < e; ++i) cout << s[i] << ' ';
}
int get() {
  int m;
  cin >> m;
  if (m < 0) exit(0);
  return m;
}
void split(int u, int p = 0, int t = 0) {
  part[t].push_back(u);
  for (int v : adj[u])
    if (v != p) split(v, u, t ^ 1);
}
pair<int, int> find_edge(const vector<int> &s, int bs, int es) {
  if (es - bs == 2) return make_pair(s[bs], s[bs + 1]);
  int ms = (bs + es) / 2;
  int fl = 0, fr = 0;
  int vl, vr, b, e;
  if (ms - bs > 1) {
    cout << "? " << ms - bs << endl;
    pri(s, bs, ms);
    cout << endl;
    fl = get();
  }
  if (fl) return find_edge(s, bs, ms);
  if (es - ms > 1) {
    cout << "? " << es - ms << endl;
    pri(s, ms, es);
    cout << endl;
    fr = get();
  }
  if (fr) return find_edge(s, ms, es);
  b = bs;
  e = ms;
  while (b + 1 < e) {
    int m = (b + e) / 2;
    cout << "? " << m - b + es - ms << endl;
    pri(s, b, m);
    pri(s, ms, es);
    cout << endl;
    int flr = get();
    if (flr)
      e = m;
    else
      b = m;
  }
  vl = s[b];
  b = ms;
  e = es;
  while (b + 1 < e) {
    int m = (b + e) / 2;
    cout << "? " << m - b + 1 << endl;
    pri(s, b, m);
    cout << vl << endl;
    int flr = get();
    if (flr)
      e = m;
    else
      b = m;
  }
  vr = s[b];
  return make_pair(vl, vr);
}
bool dfs(int u, int dst, int p = 0) {
  if (u == dst) return path.push_back(u), true;
  for (int v : adj[u]) {
    if (v == p) continue;
    if (dfs(v, dst, u)) return path.push_back(u), true;
  }
  return false;
}
int main() {
  canhazfast();
  int n, fy;
  cin >> n;
  x.push_back(1);
  for (int i = 2; i <= n; ++i) y.push_back(i);
  fy = 0;
  if (y.size() > 1) {
    cout << "? " << y.size() << endl << y << endl;
    fy = get();
  }
  for (int i = 0; i < n - 1; ++i) {
    int u = x[i];
    cout << "? " << y.size() + 1 << endl << y << u << endl;
    int cnt = get() - fy;
    if (!cnt) continue;
    while (cnt) {
      int b = 0, e = (int)y.size();
      while (b + 1 < e) {
        int m = (b + e) / 2;
        int fl = 0, flu = 0;
        if (m - b > 1) {
          cout << "? " << m - b << endl;
          pri(y, b, m);
          cout << endl;
          fl = get();
        }
        cout << "? " << m - b + 1 << endl;
        pri(y, b, m);
        cout << u << endl;
        flu = get();
        if (fl < flu)
          e = m;
        else
          b = m;
      }
      int v = y[b];
      x.push_back(v);
      y.erase(find((y).begin(), (y).end(), v));
      adj[u].push_back(v);
      adj[v].push_back(u);
      --cnt;
    }
    if (y.empty()) break;
    fy = 0;
    if (y.size() > 1) {
      cout << "? " << y.size() << endl << y << endl;
      fy = get();
    }
  }
  split(1);
  if (part[0].size() > part[1].size()) swap(part[0], part[1]);
  for (int i : {0, 1}) {
    if (part[i].size() < 2) continue;
    cout << "? " << part[i].size() << endl << part[i] << endl;
    int f = get();
    if (f == 0) continue;
    pair<int, int> e = find_edge(part[i], 0, (int)part[i].size());
    dfs(e.first, e.second);
    cout << "N " << path.size() << endl << path << endl;
    return 0;
  }
  cout << "Y " << part[0].size() << endl << part[0] << endl;
  return 0;
}
