//#define NDEBUG
#include <cstddef>
#include <cstdint>
#include <vector>

namespace n91 {

using i8 = std::int_fast8_t;
using i32 = std::int_fast32_t;
using i64 = std::int_fast64_t;
using u8 = std::uint_fast8_t;
using u32 = std::uint_fast32_t;
using u64 = std::uint_fast64_t;
using isize = std::ptrdiff_t;
using usize = std::size_t;

constexpr usize operator"" _z(unsigned long long x) noexcept {
  return static_cast<usize>(x);
}

class rep {
  const usize f, l;

public:
  class itr {
    friend rep;
    usize i;
    constexpr itr(const usize x) noexcept : i(x) {}

  public:
    void operator++() noexcept { ++i; }
    constexpr usize operator*() const noexcept { return i; }
    constexpr bool operator!=(const itr x) const noexcept { return i != x.i; }
  };
  constexpr rep(const usize first, const usize last) noexcept
      : f(first), l(last) {}
  constexpr itr begin() const noexcept { return itr(f); }
  constexpr itr end() const noexcept { return itr(l); }
};
class revrep {
  const usize f, l;

public:
  class itr {
    friend revrep;
    usize i;
    constexpr itr(usize x) noexcept : i(x) {}

  public:
    void operator++() noexcept { --i; }
    constexpr usize operator*() const noexcept { return i; }
    constexpr bool operator!=(const itr x) const noexcept { return i != x.i; }
  };
  constexpr revrep(usize first, usize last) noexcept : f(--first), l(--last) {}
  constexpr itr begin() const noexcept { return itr(l); }
  constexpr itr end() const noexcept { return itr(f); }
};
template <class T> using vec_alias = std::vector<T>;
template <class T> auto md_vec(const usize n, const T &value) {
  return std::vector<T>(n, value);
}
template <class... Args> auto md_vec(const usize n, Args... args) {
  return std::vector<decltype(md_vec(args...))>(n, md_vec(args...));
}
template <class T> constexpr T difference(const T &a, const T &b) {
  return a < b ? b - a : a - b;
}

} // namespace n91

#include <algorithm>
#include <iostream>
#include <queue>
#include <utility>

namespace n91 {

bool q(const usize x, const usize y) {
  std::cout << "? " << x + 1_z << " " << y + 1_z << std::endl;
  usize ret;
  std::cin >> ret;
  return ret - 1_z == x;
}

void answer(const usize x) { std::cout << "! " << x + 1_z << std::endl; }

void main_() {
  usize n;
  std::cin >> n;

  struct train {
    usize a;
    std::vector<usize> b;
    explicit train(const usize a) : a(a), b() {}
  };

  std::queue<train> ts;
  for (const auto i : rep(0_z, n)) {
    ts.emplace(i);
  }

  while (ts.size() != 1_z) {
    auto fst = ts.front();
    ts.pop();
    auto snd = ts.front();
    ts.pop();
    if (q(fst.a, snd.a)) {
      std::swap(fst, snd);
    }
    snd.b.push_back(fst.a);
    ts.push(std::move(snd));
  }

  const auto top = ts.front();

  answer(*std::min_element(top.b.cbegin(), top.b.cend(),
                           [](auto l, auto r) { return q(l, r); }));
}

} // namespace n91

int main() {
  n91::main_();
  return 0;
}