Language: C++

#pragma GCC diagnostic ignored "-Wunused-variable" 
#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
//using namespace atcoder;

#define BOOST
#ifdef BOOST
#include <boost/multiprecision/cpp_int.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
using namespace boost;
using ml = multiprecision::cpp_int;
using md = multiprecision::cpp_dec_float_100;
#endif

/***** type *****/
using ll = long long;
using ld = long double;
using pll = pair<long long, long long>;
template <class T> using vt = vector<T>;
template <class T> using vvt = vector<vector<T>>;
template <class T> using vvvt = vector<vector<vector<T>>>;
/***** define *****/
#define all(c) (c).begin(), (c).end()            // begin to end
#define coutld cout << fixed << setprecision(10) // cout double
#define output(x) do { cout << x << endl; exit(0); } while(0)
#define rep(i, b, e) for (ll i = b; i < e; i++)  // repeat
#define repr(i, b, e) for (ll i = b; e < i; i--) // repeat reverse
#define fori(i, ...) if (ll i = -1) for(__VA_ARGS__) if (i++, 1)
#define each(i, e, c) fori (i, auto&& e: c)      // for each
/***** const value *****/
#define llong_max 9223372036854775807            // 9 * 10^18
#define ldbl_max 1.79769e+308                    // 1.7 * 10^308
#define pi 3.1415926535897932                    // 3.14 ...
/***** lambda *****/
auto Ceil = [] // if (a % b != 0) return a / b + 1;
(auto x) { return (ll)ceil(x); };
auto Count = [] // long long count value
(auto b, auto e, auto x) { return (ll)count(b, e, x); };
auto CtoL = [] // char to number
(auto c) { return (ll)c - (ll)'0'; };
auto LtoC = [] // number to char
(auto n) { return (char)('0' + n); };
auto Pow = [] // long long pow
(auto a, auto b) { return (ll)pow(a, b); };
auto Pow2 = [] // long long pow2
(auto n) { return (1LL << n); };
auto Pow10 = [] // long long pow10
(auto n) { return (ll)pow(10, n); };
auto Size = []  // long long collection size
(auto& c) { return (ll)(c).size(); };
auto Sum = [] // long long accumulate
(auto b, auto e) { return accumulate(b, e, 0LL); };

/***** operator *****/
template <class T, class S> pair<T, S> operator + (pair<T, S> l, pair<T, S> r)
{	// pair<T, S> + pair<T, S>
	return { l.first + r.first, l.second + r.second };
}
template <class T, class S> pair<T, S> operator - (pair<T, S> l, pair<T, S> r)
{	// pair<T, S> - pair<T, S>
	return { l.first - r.first, l.second - r.second };
}

/***** template *****/
template <class T> void MakeVVT
(ll ys, ll xs, vvt<T>& v, T fill = T())
{	// vector<vector<T>> resize + fill
	v.resize(ys); rep(y, 0, ys) v[y].resize(xs, fill);
}
template <class T> void MakeVVVT
(ll zs, ll ys, ll xs, vvvt<T>& v, T fill = T())
{	// vector<vector<vector<T>>> resize + fill
	v.resize(zs); rep(z, 0, zs) MakeVVT(ys, xs, v[z], fill);
}
template <class T> void InputVVT
(ll ys, ll xs, vvt<T>& v, T fix = T())
{	// input vector<vector<T>> (T != struct) + fix
	MakeVVT(ys, xs, v, fix);
	rep(y, 0, ys) rep(x, 0, xs) { cin >> v[y][x]; v[y][x] += fix; }
}
template <class T> void InputVVVT
(ll zs, ll ys, ll xs, vvvt<T>& v, T fix = T())
{	// input vector<vector<vector<T>>> (T != struct) + fix
	v.resize(zs); rep(z, 0, zs) InputVVT(ys, xs, v[z], fix);
}

/**************************************/
/********** BEGIN OF NYA LIB **********/
/**************************************/

namespace NyaGadget {}

namespace NyaGadget
{
	/*** めぐる式二分探索ライブラリ ***/

	struct MeguruSearchResult
	{	// 二分探索の結果を格納する
		long long ok_start = 0;  // okとなる最小値
		long long ok_end = 0;    // okとなる最大値
	};

	struct NT_MeguruSeach
	{
		MeguruSearchResult res;

		bool IsOK(long long mid)
		{	// 問題毎に新しく定義する
			return (mid) ? true : false;
		}

		/*
		@brief 二分探索関数
		@param rmin 探索範囲最小値
		@param rmax 探索範囲最大値
		@param res 結果を格納する構造体
		@note
		 rmin < rmax になるように探索範囲を指定すること。
		*/
		void Run(long long rmin, long long rmax, MeguruSearchResult& res)
		{	// 半開区間 (ng, ok] or [ok, ng) で処理する
			long long ng, ok;
			if (IsOK(rmin) && IsOK(rmax)) { res = { rmin, rmax, rmax - rmin + 1 }; return; }
			else if (IsOK(rmin) && !IsOK(rmax)) { ng = rmax + 1; ok = rmin; }
			else if (!IsOK(rmin) && IsOK(rmax)) { ng = rmin - 1; ok = rmax; }
			else { res = { 0, 0, 0 }; return; }

			while (1 < abs(ok - ng))
			{	// okとngのどちらが大きいかわからないことを考慮して絶対値を取る
				long long mid = (ok + ng) / 2;
				if (IsOK(mid)) ok = mid;
				else ng = mid;
			}

			if (ng < ok) res = { ng + 1, ok, abs(ok - ng) };
			else         res = { ok, ng - 1, abs(ok - ng) };
		}

		///////////////////////////
		// key を利用した二分探索
		///////////////////////////

		bool IsOK(long long mid, string key)
		{	// 問題毎に新しく定義する
			cout << mid << endl;
			string test; cin >> test;
			if (test == "Vacant") exit(0);
			if (mid % 2 == 0 && test == key) return true;
			else if (mid % 2 != 0 && test != key) return true;
			return false;
		}

		decltype(res)& Run(pll range, long long ok_start, string key)
		{
			long long ok = ok_start;
			long long ng = (ok_start == range.first) ? range.second + 1 : range.first - 1;

			/* ok と ng のどちらが大きいかわからないことを考慮 */
			while (abs(ok - ng) > 1)
			{
				long long mid = (ok + ng) / 2;
				if (IsOK(mid, key)) ok = mid;
				else ng = mid;
			}
			res = {ok_start, ok};
			return res;
		}
	};
}

/**************************************/
/*********** END OF NYA LIB ***********/
/**************************************/

using namespace NyaGadget;
//using mll = NT_ModLL< 1000000007 >;
//using mll = NT_ModLL< 998244353 >;

int main(void)
{
	ll N; cin >> N;

	//MeguruSearchResult res;
	NT_MeguruSeach ms;
	cout << N - 1 << endl;
	string test; cin >> test;
	if (test == "Vacant") return 0;
	cout << 0 << endl;
	test.clear(); cin >> test;
	if (test == "Vacant") return 0;
	auto res = ms.binary_search({0, N-1}, 0, test);

	cout << res.ok_end + 1 << endl;
	test.clear(); cin >> test;
	if (test == "Vacant") return 0;
	return 0;
}


Compiler output:
a.cc:9:10: fatal error: boost/multiprecision/cpp_int.hpp: No such file or directory
    9 | #include <boost/multiprecision/cpp_int.hpp>
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.