Submission #718065

#	Time	Username	Problem	Language	Result	Execution time	Memory
718065		Johann	Two Antennas (JOI19_antennas)	C++14	100 / 100	526 ms	38080 KiB

antennas

#include <bits/stdc++.h>
using namespace std;

#define pii pair<int, int>
#define tiii tuple<int, int, int>
#define vi vector<int>
#define vvi vector<vi>
#define vb vector<bool>
#define vpii vector<pii>
#define vtiii vector<tiii>
#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

struct item
{
    int res = -1;
    int ap = INT_MIN, an = INT_MIN; // apply operation
    int bp = INT_MAX, bn = INT_MAX; // what is contained in the Stuff
};

struct SegTree
{
    int size;
    vector<item> arr;
    void init(vi &H)
    {
        size = 1;
        while (size < sz(H))
            size *= 2;
        arr.assign(2 * size, item());
    }
    void combine(int x)
    {
        assert(arr[x].ap == INT_MIN && arr[x].an == INT_MIN);
        assert(x < size);
        arr[x].res = max(arr[2 * x].res, arr[2 * x + 1].res);
        arr[x].bp = min(arr[2 * x].bp, arr[2 * x + 1].bp);
        arr[x].bn = min(arr[2 * x].bn, arr[2 * x + 1].bn);
    }
    void apply(int x, int ap, int an)
    {
        arr[x].ap = max(arr[x].ap, ap);
        arr[x].an = max(arr[x].an, an);
        if (arr[x].ap != INT_MIN && arr[x].bp != INT_MAX)
            arr[x].res = max(arr[x].res, arr[x].ap - arr[x].bp);
        if (arr[x].an != INT_MIN && arr[x].bn != INT_MAX)
            arr[x].res = max(arr[x].res, arr[x].an - arr[x].bn);
    }
    void propagate(int x)
    {
        if (x < size)
            apply(2 * x, arr[x].ap, arr[x].an), apply(2 * x + 1, arr[x].ap, arr[x].an);
        arr[x].ap = arr[x].an = INT_MIN;
    }
    void update(int i, int bp, int bn, int x, int lx, int rx)
    {
        if (rx - lx == 1)
        {
            arr[x].ap = arr[x].an = INT_MIN;
            arr[x].bp = bp, arr[x].bn = bn;
            return;
        }
        propagate(x);
        int m = (lx + rx) / 2;
        if (i < m)
            update(i, bp, bn, 2 * x, lx, m);
        else
            update(i, bp, bn, 2 * x + 1, m, rx);
        combine(x);
    }
    void update(int i, int bp, int bn)
    {
        update(i, bp, bn, 1, 0, size);
    }
    void applyA(int l, int r, int ap, int an)
    {
        applyA(l, r, ap, an, 1, 0, size);
    }
    void applyA(int l, int r, int ap, int an, int x, int lx, int rx)
    {
        if (rx <= l || r <= lx)
            return;
        if (l <= lx && rx <= r)
        {
            apply(x, ap, an);
            return;
        }
        propagate(x);
        int m = (lx + rx) / 2;
        applyA(l, r, ap, an, 2 * x, lx, m);
        applyA(l, r, ap, an, 2 * x + 1, m, rx);
        combine(x);
    }
    int query(int l, int r, int x, int lx, int rx)
    {
        if (rx <= l || r <= lx)
            return -1;
        if (l <= lx && rx <= r)
            return arr[x].res;
        propagate(x);
        int m = (lx + rx) / 2;
        int a = query(l, r, 2 * x, lx, m);
        int b = query(l, r, 2 * x + 1, m, rx);
        return max(a, b);
    }
    int query(int l, int r)
    {
        return query(l, r, 1, 0, size);
    }
};

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    int n;
    cin >> n;
    vi H(n), A(n), B(n);
    vvi toAct(n + 1);
    vvi toDea(n + 1);
    for (int i = 0; i < n; ++i)
    {
        cin >> H[i] >> A[i] >> B[i];
        if (i + A[i] < n)
            toAct[i + A[i]].push_back(i);
        if (i + B[i] + 1 < n)
            toDea[i + B[i] + 1].push_back(i);
    }

    int q;
    cin >> q;
    vtiii Q(q);
    for (int i = 0, l, r; i < q; ++i)
    {
        cin >> l >> r;
        --l, --r;
        Q[i] = {l, r, i};
    }
    sort(all(Q), [&](tiii &a, tiii &b)
         { return get<1>(a) > get<1>(b); }); // Niedrige Endpunkte nach hinten, dann kann man den Vektor als queue verwenden
    vi ans(q, -1);

    SegTree seg;
    seg.init(H);

    vb active(n, false);
    for (int i = 0; i < n; ++i)
    {
        for (int j : toAct[i])
            seg.update(j, H[j], -H[j]);
        for (int j : toDea[i])
            seg.update(j, INT_MAX, INT_MAX);

        seg.applyA(i - B[i], i - A[i] + 1, H[i], -H[i]);

        while (!Q.empty() && get<1>(Q.back()) == i)
        {
            int l, r, idx;
            tie(l, r, idx) = Q.back();
            Q.pop_back();
            ans[idx] = seg.query(l, r);
        }
    }

    for (int x : ans)
        cout << x << "\n";
}

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