oj.uz

답안 #655413

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
655413 2022-11-04T09:50:38 Z piOOE 3단 점프 (JOI19_jumps) C++17
0 / 100
 104 ms 104444 KB 
#include <bits/stdc++.h>

using namespace std;

constexpr int inf = 1e9 + 7;

vector<vector<int>> mst;

vector<int> a;

bool cmp(int i, int j) {
    return a[i] > a[j] ? i : j;
}

int sz = 1;

void init(vector<int> b) {
    sz = 1;
    while (sz < b.size()) sz <<= 1;
    mst.resize(sz * 2);
    for (int i = 0; i < int(b.size()); ++i) {
        mst[i + sz] = {i};
    }
    for (int i = sz - 1; i > 0; --i) {
        mst[i].resize(mst[i << 1].size() + mst[i << 1 | 1].size());
        merge(mst[i << 1].begin(), mst[i << 1].end(), mst[i << 1 | 1].begin(), mst[i << 1 | 1].end(), mst[i].begin(), cmp);
    }
}

vector<int> d;

void getSorted(int l, int r, int cnt, int x = 1, int lx = 0, int rx = sz) {
    if (l >= rx || lx >= r) return;
    if (l <= lx && rx <= r) {
        d.insert(d.end(), mst[x].begin(), mst[x].begin() + min(cnt, int(mst[x].size())));
        return;
    }
    int mid = (lx + rx) >> 1;
    getSorted(l, r, cnt, x << 1, lx, mid);
    getSorted(l, r, cnt, x << 1 | 1, mid, rx);
}

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

    int n;
    cin >> n;

    a.resize(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))]);
        }
    }

    init(a);

    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;

        d.clear();
        getSorted(l, r, 30);
        sort(d.begin(), d.end(), cmp);
        d.resize(min(int(d.size()), 30));
        swap(p, d);

        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)]);
            }
        };

        sort(p.begin(), p.end());

        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;
}

Compilation message

jumps.cpp: In function 'void init(std::vector<int>)':
jumps.cpp:19:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |     while (sz < b.size()) sz <<= 1;
      |            ~~~^~~~~~~~~~

Subtask #1
0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Runtime error 1 ms 468 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #2
0 / 14.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Runtime error 1 ms 468 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 104 ms 104444 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #4
0 / 54.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Runtime error 1 ms 468 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -