Submission #685111

#	Time	Username	Problem	Language	Result	Execution time	Memory
685111		stanislavpolyn	Colors (BOI20_colors)	C++17	9 / 100	2 ms	304 KiB

Colors

#include <bits/stdc++.h>

#define fr(i, a, b) for (int i = (a); i <= (b); ++i)
#define rf(i, a, b) for (int i = (a); i >= (b); --i)
#define fe(x, y) for (auto& x : y)

#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple

#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define pw(x) (1LL << (x))

using namespace std;

mt19937_64 rng(228);

#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template <typename T>
using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define fbo find_by_order
#define ook order_of_key

template <typename T>
bool umx(T& a, T b) {
    return a < b ? a = b, 1 : 0;
}
template <typename T>
bool umn(T& a, T b) {
    return a > b ? a = b, 1 : 0;
}

using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
template <typename T>
using ve = vector<T>;

#ifdef LOCAL
const bool DEBUG = 1;
#else
const bool DEBUG = 0;
#endif

ll n, C;
set<ll> used;
ll last;

bool ask(ll x) {
    assert(!used.count(x));
    used.insert(x);
    cout << "? " << x << "\n" << flush;

    if (DEBUG) {
        if (abs(x - last) >= C) {
            last = x;
            return 1;
        } else {
            last = x;
            return 0;
        }
    }
    last = x;
    int val;
    cin >> val;

    return val;
}

int main() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#else
//    ios::sync_with_stdio(0);
//    cin.tie(0);
#endif

    cin >> n;

    if (DEBUG) {
        cin >> C;
    }

    ask(1);
    bool who = 0;
    rf (now, n - 1, 1) {

        if (who == 0) {
            if (!ask(last + now)) {
                cout << "= " << now + 1 << "\n";
                return 0;
            }
        } else {
            if (!ask(last - now)) {
                cout << "= " << now + 1 << "\n";
                return 0;
            }
        }

        who ^= 1;
    }

    cout << "= " << 1 << "\n";

    return 0;
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 33