Submission #749674

#	Time	Username	Problem	Language	Result	Execution time	Memory
749674		finn__	Teams (CEOI11_tea)	C++17	40 / 100	2567 ms	40008 KiB

tea

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

constexpr size_t N = 1000001, L = 1 << 20;

size_t n;
pair<int, int> a[N];
int tree[2 * L][2], f[N], pre[N];

void update(size_t i, int x, int y)
{
    i += L;
    tree[i][0] = x;
    tree[i][1] = y;
    while (i >>= 1)
    {
        tree[i][0] = max(tree[i << 1][0], tree[(i << 1) | 1][0]);
        tree[i][1] = tree[i << 1][0] > tree[(i << 1) | 1][0] ? tree[i << 1][1] : tree[(i << 1) | 1][1];
    }
}

pair<int, int> range_max(size_t i, size_t j)
{
    i += L, j += L;
    int x = 0, y = 0;
    while (i <= j)
    {
        if (i & 1)
        {
            y = tree[i][0] > x ? tree[i][1] : y;
            x = max(x, tree[i++][0]);
        }
        if (!(j & 1))
        {
            y = tree[j][0] > x ? tree[j][1] : y;
            x = max(x, tree[j--][0]);
        }
        i >>= 1;
        j >>= 1;
    }
    return {x, y};
}

int max_number_of_teams(size_t max_team_size)
{
    memset(tree, 0, sizeof tree);
    for (size_t i = 1; i <= n; ++i)
        if (i >= a[i].first)
        {
            size_t u = i - min(max_team_size, i), v = i - a[i].first;
            auto const [x, y] = range_max(u, v);
            f[i] = x + 1, pre[i] = y;
            update(i, x + 1, i);
        }
    return f[n];
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for (size_t i = 1; i <= n; ++i)
        cin >> a[i].first, a[i].second = i;
    sort(a + 1, a + n + 1);

    int t = max_number_of_teams(n);
    cout << t << '\n';
    size_t u = a[n].first, v = n;
    while (u < v)
    {
        size_t mid = (u + v) / 2;
        if (max_number_of_teams(mid) == t)
            v = mid;
        else
            u = mid + 1;
    }

    max_number_of_teams(u);
    int i = n;
    while (i)
    {
        vector<int> team;
        for (int j = pre[i] + 1; j <= i; ++j)
            team.push_back(a[j].second);
        i = pre[i];
        cout << team.size() << ' ';
        for (int &x : team)
            cout << x << ' ';
        cout << '\n';
    }
}

Compilation message (stderr)

tea.cpp: In function 'int max_number_of_teams(size_t)':
tea.cpp:48:15: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   48 |         if (i >= a[i].first)
      |             ~~^~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 10 / 10
• Subtask 7: 0 / 10
• Subtask 8: 10 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10