Submission #570140

#	Time	Username	Problem	Language	Result	Execution time	Memory
570140		timreizin	Two Antennas (JOI19_antennas)	C++17	2 / 100	3079 ms	7496 KiB

antennas

#include <iostream>
#include <vector>
#include <numeric>
#include <cmath>
#include <set>
#include <array>
#include <algorithm>

using namespace std;

using ll = long long;

const ll INF = 1e15;

struct segtree
{
    int n;
    vector<ll> mx, mod, tree;
    
    void push(int v)
    {
        mod[v << 1] = max(mod[v << 1], mod[v]);
        mod[v << 1 | 1] = max(mod[v << 1 | 1], mod[v]);
        tree[v << 1] = max(tree[v << 1], mx[v << 1] + mod[v]);
        tree[v << 1 | 1] = max(tree[v << 1 | 1], mx[v << 1 | 1] + mod[v]);
    }
    
    segtree(int n) : n(n)
    {
        mx.resize(4 * n, -INF);
        mod.resize(4 * n, 0);
        tree.resize(4 * n, -INF);
    }
    
    ll get(int a, int b, int l, int r, int v)
    {
        if (a > r || b < l) return -INF;
        if (a == l && b == r) return tree[v];
        int m = (l + r) >> 1;
        push(v);
        return max(get(a, min(b, m), l, m, v << 1), get(max(a, m + 1), b, m + 1, r, v << 1 | 1));
    }
    
    ll get(int a, int b)
    {
        return get(a, b, 0, n - 1, 1);
    }
    
    void updateH(int p, ll val, int l, int r, int v)
    {
        if (l > r) return;
        if (l == r)
        {
            mx[v] = val;
            tree[v] = val + mod[v];
            return;
        }
        int m = (l + r) >> 1;
        push(v);
        if (p <= m) updateH(p, val, l, m, v << 1);
        else updateH(p, val, m + 1, r, v << 1 | 1);
        tree[v] = max(tree[v << 1], tree[v << 1 | 1]);
        mx[v] = max(mx[v << 1], mx[v << 1 | 1]);
    }
    
    void updateH(int p, ll val)
    {
        updateH(p, val, 0, n - 1, 1);
    }
    
    void updateM(int a, int b, ll val, int l, int r, int v)
    {
        if (a > r || b < l) return;
        if (a == l && b == r)
        {
            mod[v] = max(mod[v], val);
            tree[v] = max(tree[v], mx[v] + mod[v]);
            return;
        }
        int m = (l + r) >> 1;
        push(v);
        updateM(a, min(b, m), val, l, m, v << 1);
        updateM(max(a, m + 1), b, val, m + 1, r, v << 1 | 1);
        tree[v] = max(tree[v << 1], tree[v << 1 | 1]);
        mx[v] = max(mx[v << 1], mx[v << 1 | 1]);
    }
    
    void updateM(int a, int b, ll val)
    {
        updateM(a, b, val, 0, n - 1, 1);
    }
    
};

vector<ll> solve(vector<ll> h, vector<pair<int, int>> ab, vector<pair<int, int>> queries)
{
    int n = (int)h.size();
    int q = (int)queries.size();
    vector<int> inds(q);
    vector<pair<pair<int, int>, int>> events;
    segtree st(n);
    events.reserve(2 * n);
    iota(inds.begin(), inds.end(), 0);
    sort(inds.begin(), inds.end(), [&queries](int a, int b){ return queries[a].second < queries[b].second; });
    for (int i = 0; i < n; ++i)
    {
        events.emplace_back(pair(i + ab[i].first, 0), i);
        events.emplace_back(pair(i + ab[i].second, 1), i);
    }
    sort(events.begin(), events.end());
    vector<ll> result(q, -1);
    for (int i = 0, indE = 0, indQ = 0; i < n; ++i)
    {
        while (indE < 2 * n && events[indE].first <= pair(i, 0))
        {
            st.updateH(events[indE].second, -h[events[indE].second]);
            ++indE;
        }
        if (i - ab[i].first >= 0) st.updateM(max(0, i - ab[i].second), i - ab[i].first, h[i]);
        while (indQ < q && queries[inds[indQ]].second == i)
        {
            result[inds[indQ]] = max(result[inds[indQ]], st.get(queries[inds[indQ]].first, queries[inds[indQ]].second));
            ++indQ;
        }
        while (indE < 2 * n && events[indE].first <= pair(i, 1))
        {
            st.updateH(events[indE].second, -INF);
            ++indE;
        }
        
    }
    reverse(h.begin(), h.end());
    reverse(ab.begin(), ab.end());
    for (auto &i : queries) i = {n - i.second - 1, n - i.first - 1};
    events.clear();
    sort(inds.begin(), inds.end(), [&queries](int a, int b){ return queries[a].second < queries[b].second; });
    for (int i = 0; i < n; ++i)
    {
        events.emplace_back(pair(i + ab[i].first, 0), i);
        events.emplace_back(pair(i + ab[i].second, 1), i);
    }
    sort(events.begin(), events.end());
    st = segtree(n);
    for (int i = 0, indE = 0, indQ = 0; i < n; ++i)
    {
        while (indE < 2 * n && events[indE].first <= pair(i, 0))
        {
            st.updateH(events[indE].second, -h[events[indE].second]);
            ++indE;
        }
        if (i - ab[i].first >= 0) st.updateM(max(0, i - ab[i].second), i - ab[i].first, h[i]);
        while (indQ < q && queries[inds[indQ]].second == i)
        {
            result[inds[indQ]] = max(result[inds[indQ]], st.get(queries[inds[indQ]].first, queries[inds[indQ]].second));
            ++indQ;
        }
        while (indE < 2 * n && events[indE].first <= pair(i, 1))
        {
            st.updateH(events[indE].second, -INF);
            ++indE;
        }
    }
    return result;
}

vector<ll> brute(vector<ll> h, vector<pair<int, int>> ab, vector<pair<int, int>> queries)
{
    int n = (int)h.size();
    int q = (int)queries.size();
    vector<ll> res(q, -1);
    for (int i = 0; i < q; ++i)
    {
        for (int j = queries[i].first; j <= queries[i].second; ++j)
        {
            for (int k = j + ab[j].first; k <= min(queries[i].second, j + ab[j].second); ++k)
            {
                if (k - j >= ab[k].first && k - j <= ab[k].second) res[i] = max(res[i], abs(h[j] - h[k]));
            }
        }
        cout << res[i] << '\n';
    }
    return res;
}

int main()
{
    cin.tie(0)->sync_with_stdio(0);
    int n;
    cin >> n;
    vector<ll> h(n);
    vector<pair<int, int>> ab(n);
    for (int i = 0; i < n; ++i)
    {
        cin >> h[i] >> ab[i].first >> ab[i].second;
    }
    int q;
    cin >> q;
    vector<pair<int, int>> queries(q);
    for (auto &[l, r] : queries)
    {
        cin >> l >> r;
        --l;
        --r;
    }
    brute(h, ab, queries);
    return 0;
}
/*
 5
 10 2 4
 1 1 1
 2 1 3
 1 1
 1
 100 1 1
 5
 1 2
 2 3
 1 3
 1 4
 1 5
 */

/*
2
10 2 4
1 1 1
1
1 2
*/
//10 1 2 1 100

Compilation message (stderr)

antennas.cpp: In function 'std::vector<long long int> brute(std::vector<long long int>, std::vector<std::pair<int, int> >, std::vector<std::pair<int, int> >)':
antennas.cpp:168:9: warning: unused variable 'n' [-Wunused-variable]
  168 |     int n = (int)h.size();
      |         ^

• Subtask 1: 2 / 2
• Subtask 2: 0 / 11
• Subtask 3: 0 / 22
• Subtask 4: 0 / 65