Language: C++

#include "bits/stdc++.h"

// Begin Header {{{
using namespace std;

#ifndef DEBUG
#define dump(...)
#endif

#define all(x) x.begin(), x.end()
#define rep(i, b, e) for (intmax_t i = (b), i##_limit = (e); i < i##_limit; ++i)
#define reps(i, b, e) for (intmax_t i = (b), i##_limit = (e); i <= i##_limit; ++i)
#define repr(i, b, e) for (intmax_t i = (b), i##_limit = (e); i >= i##_limit; --i)
#define var(Type, ...) Type __VA_ARGS__; input(__VA_ARGS__)

constexpr size_t    operator""_zu(unsigned long long value) { return value; };
constexpr intmax_t  operator""_jd(unsigned long long value) { return value; };
constexpr uintmax_t operator""_ju(unsigned long long value) { return value; };

constexpr int INF = 0x3f3f3f3f;
constexpr intmax_t LINF = 0x3f3f3f3f3f3f3f3f_jd;

template <class T, class Compare = less<>>
using MaxHeap = priority_queue<T, vector<T>, Compare>;
template <class T, class Compare = greater<>>
using MinHeap = priority_queue<T, vector<T>, Compare>;

inline void input() {}
template <class Head, class... Tail>
inline void input(Head&& head, Tail&&... tail) {
    cin >> head;
    input(forward<Tail>(tail)...);
}

template <class T>
inline istream& operator>>(istream &is, vector<T> &vec) {
    for (auto &e: vec) {
        is >> e;
    }
    return is;
}

inline void output() { cout << "\n"; }
template <class Head, class... Tail>
inline void output(Head&& head, Tail&&... tail) {
    cout << head;
    if (sizeof...(tail)) {
        cout << " ";
    }
    output(forward<Tail>(tail)...);
}

template <class T>
inline ostream& operator<<(ostream &os, const vector<T> &vec) {
    static constexpr const char *delim[] = {" ", ""};
    for (const auto &e: vec) {
        os << e << delim[&e == &vec.back()];
    }
    return os;
}

template <class T>
inline vector<T> makeVector(const T &initValue, size_t sz) {
    return vector<T>(sz, initValue);
}

template <class T, class... Args>
inline auto makeVector(const T &initValue, size_t sz, Args... args) {
    return vector<decltype(makeVector<T>(initValue, args...))>(sz, makeVector<T>(initValue, args...));
}

template <class Func>
class FixPoint : Func {
public:
    explicit constexpr FixPoint(Func&& f) noexcept : Func(forward<Func>(f)) {}

    template <class... Args>
    constexpr decltype(auto) operator()(Args&&... args) const {
        return Func::operator()(*this, std::forward<Args>(args)...);
    }
};

template <class Func>
static inline constexpr decltype(auto) makeFixPoint(Func&& f) noexcept {
    return FixPoint<Func>{forward<Func>(f)};
}

template <class Container>
struct reverse_t {
    Container &c;
    reverse_t(Container &c) : c(c) {}
    auto begin() { return c.rbegin(); }
    auto end() { return c.rend(); }
};

template <class Container>
auto reversed(Container &c) {
    return reverse_t<Container>(c);
}

template <class T>
inline bool chmax(T &a, const T &b) noexcept {
    return b > a && (a = b, true);
}

template <class T>
inline bool chmin(T &a, const T &b) noexcept {
    return b < a && (a = b, true);
}

template <class T>
inline T diff(const T &a, const T &b) noexcept {
    return a < b ? b - a : a - b;
}
// End Header }}}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    var(intmax_t, N);

    vector<int> stat(N, -1);

    const auto ask = [](const int i) {
        cout << i << endl;
        var(string, s);
        if (s == "Vacant") return stat[i] = 0;
        else if (s == "Male") return stat[i] = 1;
        else return stat[i] = 2;
    };

    if (ask(0) == 0) return 0;

    int left = 0, right = N;
    int cnt = 0;
    while (++cnt <= 20 && right - left > 1) {
        const int mid = (right + left) / 2;
        if (ask(mid) == 0) return 0;

        if ((stat[left] == stat[mid]) == ((mid - left) & 1)) {
            right = mid;
        } else {
            left = mid;
        }
    }

    return 0;
}


Compiler output:
a.cc: In lambda function:
a.cc:128:35: error: 'stat' is not captured
  128 |         if (s == "Vacant") return stat[i] = 0;
      |                                   ^~~~
a.cc:125:23: note: the lambda has no capture-default
  125 |     const auto ask = [](const int i) {
      |                       ^
a.cc:123:17: note: 'std::vector<int> stat' declared here
  123 |     vector<int> stat(N, -1);
      |                 ^~~~
a.cc:129:38: error: 'stat' is not captured
  129 |         else if (s == "Male") return stat[i] = 1;
      |                                      ^~~~
a.cc:125:23: note: the lambda has no capture-default
  125 |     const auto ask = [](const int i) {
      |                       ^
a.cc:123:17: note: 'std::vector<int> stat' declared here
  123 |     vector<int> stat(N, -1);
      |                 ^~~~
a.cc:130:21: error: 'stat' is not captured
  130 |         else return stat[i] = 2;
      |                     ^~~~
a.cc:125:23: note: the lambda has no capture-default
  125 |     const auto ask = [](const int i) {
      |                       ^
a.cc:123:17: note: 'std::vector<int> stat' declared here
  123 |     vector<int> stat(N, -1);
      |                 ^~~~