#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 5, mod = 998244353;
template <class o>
inline void qr(o &x) {
  x = 0;
  char c = getchar();
  int f = 1;
  while (c < '0' || c > '9') {
    if (c == '-') f = -1;
    c = getchar();
  }
  while (c >= '0' && c <= '9') {
    x = x * 10 + (c ^ 48);
    c = getchar();
  }
  x *= f;
}
template <class o>
void qw(o x) {
  if (x / 10) qw(x / 10);
  putchar(x % 10 + 48);
}
template <class o>
void pr1(o x) {
  if (x < 0) putchar('-'), x = -x;
  qw(x);
  putchar(' ');
}
template <class o>
void pr2(o x) {
  if (x < 0) putchar('-'), x = -x;
  qw(x);
  puts("");
}
inline int ksm(int a, int b = mod - 2) {
  int ans = 1;
  for (; b; b >>= 1, a = 1ll * a * a % mod)
    if (b & 1) ans = 1ll * ans * a % mod;
  return ans;
}
inline int add(int a, int b) { return a += b, a >= mod ? a - mod : a; }
inline int sub(int a, int b) { return a -= b, a < 0 ? a + mod : a; }
pair<int, int> p[N];
int fa[N];
bool ft[N];
int a[N], cnt = 0;
int ask(int l, int r, int i) {
  cnt = 0;
  for (int i = l; i <= r; ++i)
    if (!ft[p[i].second]) a[++cnt] = p[i].second;
  if (!cnt) return 0;
  printf("1\n1\n", i);
  printf("%d\n", cnt);
  for (int i = 1; i <= cnt; ++i) printf("%d ", a[i]);
  printf("\n%d\n", i);
  fflush(stdout);
  int x;
  qr(x);
  return x;
}
void query(int l, int r, int k, int x) {
  if (l == r) {
    ft[p[l].second] = 1;
    fa[p[l].second] = x;
    return;
  }
  int mid = l + r >> 1;
  int t = ask(l, mid, x);
  if (t) query(l, mid, t, x);
  if (k > t) query(mid + 1, r, k - t, x);
}
void solve() {
  int n;
  qr(n);
  for (int i = 2; i <= n; ++i) {
    printf("1\n1\n");
    cnt = 0;
    printf("%d\n", n - 1);
    for (int i = 2; i <= n; ++i) printf("%d ", i);
    printf("\n%d\n", i);
    fflush(stdout);
    int x;
    qr(x);
    p[i - 1] = make_pair(x, i);
  }
  sort(p + 1, p + n);
  for (int i = 2; i <= n - 1; ++i) {
    int x = ask(1, i - 1, p[i].second);
    if (!x) continue;
    query(1, i - 1, x, p[i].second);
  }
  puts("ANSWER");
  for (int i = 2; i <= n; ++i) {
    printf("%d %d\n", fa[i] ? fa[i] : 1, i);
  }
  fflush(stdout);
}
int main() {
  solve();
  return 0;
}
