제출 #655418

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
655418		piOOE	3단 점프 (JOI19_jumps)	C++17	0 / 100	30 ms	14944 KiB

jumps

#include <bits/stdc++.h>

using namespace std;

constexpr int inf = 1e9 + 7;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin >> n;

    vector<int> a(n);
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
    }

    auto func = [&](int i, int j) {
        return a[i] > a[j] ? i : j;
    };

    const int max_log = __lg(n) + bool(n & (n - 1));
    vector<vector<int>> st(max_log);
    st[0].resize(n);
    iota(st[0].begin(), st[0].end(), 0);
    for (int i = 1; i < max_log; ++i) {
        st[i].resize(n - (1 << i) + 1);
        for (int j = 0; j < (int) st[i].size(); ++j) {
            st[i][j] = func(st[i - 1][j], st[i - 1][j + (1 << (i - 1))]);
        }
    }

    vector<int> logn(n + 1);
    for (int i = 2; i <= n; ++i) {
        logn[i] = logn[i >> 1] + 1;
    }

    auto query = [&](int l, int r) {
        int lg = logn[r - l];
        return func(st[lg][l], st[lg][r - (1 << lg)]);
    };

    int q;
    cin >> q;
    while (q--) {
        int l, r;
        cin >> l >> r;
        --l;
        vector<int> p{l, r};
        for (int t = 0; t < r - l && p.size() < 32; ++t) {
            int kek = -1;
            for (int i = 0; i < int(p.size()) - 1; ++i) {
                if (p[i + 1] != p[i] + 1) {
                    int d = query(p[i] + 1, p[i + 1]);
                    if (kek == -1 || a[d] > a[kek]) {
                        kek = d;
                    }
                }
            }
            if (kek == -1) {
                break;
            }
            p.insert(lower_bound(p.begin(), p.end(), kek), kek);
        }

        int ans = 0;

        auto relax = [&](int i, int j) {
            int R = j + (j - i);
            if (R < r) {
                ans = max(ans, a[i] + a[j] + a[query(R, r)]);
            }
            int len = j - i - 1;
            if (len > 0) {
                ans = max(ans, a[i] + a[j] + a[query(i + 1, i + 1 + ((len + 1) / 2))]);
            }
            int L = max(l, i - (j - i));
            if (L < i) {
                ans = max(ans, a[i] + a[j] + a[query(L, i)]);
            }
        };

        vector<int> stk;
        for (int i: p) {
            while (!stk.empty() && a[stk.back()] <= a[i]) {
                relax(stk.back(), i);
                stk.pop_back();
            }
            if (!stk.empty()) {
                relax(stk.back(), i);
            }
            stk.push_back(i);
        }

        cout << ans << '\n';
    }

    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 14
• Subtask 3: 0 / 27
• Subtask 4: 0 / 54