Submission #477188

#	Time	Username	Problem	Language	Result	Execution time	Memory
477188		Lam_lai_cuoc_doi	Triple Jump (JOI19_jumps)	C++17	100 / 100	1102 ms	88776 KiB

jumps

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;

template <class T>
void read(T &x)
{
    x = 0;
    register int c;
    while ((c = getchar()) && (c > '9' || c < '0'))
        ;
    for (; c >= '0' && c <= '9'; c = getchar())
        x = x * 10 + c - '0';
}

constexpr bool typetest = 0;

constexpr int N = 5e5 + 5;
constexpr ll Inf = 1e17;

struct SegmentTree
{
    int n;
    ll lazy[N * 4], st[N * 4], maxn[N * 4];
    SegmentTree()
    {
        fill_n(lazy, N * 4, -Inf);
        fill_n(st, N * 4, -Inf);
        fill_n(maxn, N * 4, -Inf);
    }
    void Build(int id, int l, int r, ll a[N])
    {
        if (l == r)
        {
            maxn[id] = a[l];
            return;
        }
        Build(id << 1, l, (l + r) / 2, a);
        Build(id << 1 | 1, (l + r) / 2 + 1, r, a);
        maxn[id] = max(maxn[id << 1], maxn[id << 1 | 1]);
    }
    void Build(ll a[N])
    {
        Build(1, 1, n, a);
    }

    void Push(int id)
    {
        if (lazy[id] != -Inf)
        {
            if (lazy[id << 1] < lazy[id])
            {
                lazy[id << 1] = lazy[id];
                st[id << 1] = max(st[id << 1], maxn[id << 1] + lazy[id]);
            }
            if (lazy[id << 1 | 1] < lazy[id])
            {
                lazy[id << 1 | 1] = lazy[id];
                st[id << 1 | 1] = max(st[id << 1 | 1], maxn[id << 1 | 1] + lazy[id]);
            }
            lazy[id] = -Inf;
        }
    }

    void Update(int id, int l, int r, const int &a, const int &b, const ll &v)
    {
        if (l > b || r < a)
            return;
        if (l >= a && r <= b)
        {
            if (lazy[id] < v)
            {
                lazy[id] = v;
                st[id] = max(st[id], maxn[id] + v);
            }
            return;
        }

        Push(id);

        Update(id << 1, l, (l + r) / 2, a, b, v);
        Update(id << 1 | 1, (l + r) / 2 + 1, r, a, b, v);

        st[id] = max(st[id << 1], st[id << 1 | 1]);
    }

    void Update(int l, int r, ll v)
    {
        Update(1, 1, n, l, r, v);
    }

    ll Get(int id, int l, int r, const int &a, const int &b)
    {
        if (l > b || r < a)
            return -Inf;
        if (l >= a && r <= b)
            return st[id];
        Push(id);
        return max(Get(id << 1, l, (l + r) / 2, a, b), Get(id << 1 | 1, (l + r) / 2 + 1, r, a, b));
    }

    ll Get(int l, int r)
    {
        return Get(1, 1, n, l, r);
    }
} f;

int n, q, m;
ll a[N], ans[N];
struct Query
{
    int l, r, id;
    bool operator<(const Query &a) const
    {
        return l > a.l || (l == a.l && r > a.r);
    }
} s[N], p[N * 2];

void Read()
{
    cin >> n;
    for (int i = 1; i <= n; ++i)
        cin >> a[i];
    cin >> q;
    for (int i = 1; i <= q; ++i)
        cin >> s[s[i].id = i].l >> s[i].r;
}

void Solve()
{
    f.n = n;
    f.Build(a);

    vector<int> tmp;
    for (int i = 1; i <= n; ++i)
    {
        while (!tmp.empty() && a[tmp.back()] < a[i])
            tmp.pop_back();
        if (!tmp.empty())
        {
            ++m;
            p[m].l = tmp.back();
            p[m].r = i;
        }
        tmp.emplace_back(i);
    }

    tmp.clear();

    for (int i = n; i; --i)
    {
        while (!tmp.empty() && a[tmp.back()] < a[i])
            tmp.pop_back();
        if (!tmp.empty())
        {
            ++m;
            p[m].r = tmp.back();
            p[m].l = i;
        }
        tmp.emplace_back(i);
    }

    sort(s + 1, s + q + 1);
    sort(p + 1, p + m + 1);

    for (int i = 1, j = 1; i <= q; ++i)
    {
        while (j <= m && p[j].l >= s[i].l)
        {
            f.Update(p[j].r + (p[j].r - p[j].l), n, a[p[j].l] + a[p[j].r]);
            ++j;
        }
        ans[s[i].id] = f.Get(s[i].l, s[i].r);
    }

    for (int i = 1; i <= q; ++i)
        cout << ans[i] << "\n";
}

int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t(1);
    if (typetest)
        cin >> t;
    for (int _ = 1; _ <= t; ++_)
    {
        //cout << "Case #" << _ << ": ";
        Read();
        Solve();
    }
    //cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
}

Compilation message (stderr)

jumps.cpp: In function 'void read(T&)':
jumps.cpp:12:18: warning: ISO C++17 does not allow 'register' storage class specifier [-Wregister]
   12 |     register int c;
      |                  ^

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