Submission #989117

#	Time	Username	Problem	Language	Result	Execution time	Memory
989117		aykhn	Bitaro’s Party (JOI18_bitaro)	C++17	100 / 100	1277 ms	437768 KiB

bitaro

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

const int MXN = 2e5 + 5;
const int B = 500;

int n, m, q;
vector<int> adj[MXN];
int used[MXN], dp[MXN], inq[MXN], in[MXN];
vector<array<int, 2>> b[MXN];
vector<int> o;

void init(int a)
{
    used[a] = 1;
    b[a].push_back({0, a});
    vector<array<int, 2>> nw;
    for (int v : adj[a])
    {
        if (!used[v]) init(v);
        nw.clear();
        int i = 0, j = 0;
        while (nw.size() < B + 1 && i < b[a].size() && j < b[v].size())
        {
            if (in[b[a][i][1]]) 
            {
                i++;
                continue;
            }
            if (in[b[v][j][1]])
            {
                j++;
                continue;
            }
            if (b[a][i][0] > b[v][j][0] + 1) nw.push_back(b[a][i]), in[b[a][i++][1]] = 1;
            else nw.push_back({b[v][j][0] + 1, b[v][j][1]}), in[b[v][j++][1]] = 1;
        }
        while (nw.size() < B + 1 && i < b[a].size()) if (in[b[a][i][1]] && ++i) continue; else nw.push_back(b[a][i]), in[b[a][i++][1]] = 1;
        while (nw.size() < B + 1 && j < b[v].size()) if (in[b[v][j][1]] && ++j) continue; else nw.push_back({b[v][j][0] + 1, b[v][j][1]}), in[b[v][j++][1]] = 1;
        swap(nw, b[a]);
        for (array<int, 2> &i : b[a]) in[i[1]] = 0;
    }
}
void dfs(int a)
{
    used[a] = 1;
    for (int v : adj[a])
    {
        if (used[v]) continue;
        dfs(v);
    }
    o.push_back(a);
}

void _()
{
    cin >> n >> m >> q;
    for (int i = 0; i < m; i++)
    {
        int u, v;
        cin >> u >> v;
        adj[v].push_back(u);
    }
    for (int i = n; i >= 1; i--)
    {
        if (!used[i]) init(i);
    }
    while (q--)
    {
        int t, sz;
        cin >> t >> sz;
        vector<int> v(sz);
        for (int &i : v) cin >> i, inq[i] = 1;
        if (sz > B) 
        {
            o.clear();
            for (int i = 1; i <= n; i++) used[i] = 0, dp[i] = 0;
            dfs(t);
            reverse(o.begin(), o.end());
            int res = -1;
            for (int i : o)
            {
                if (!inq[i]) res = max(res, dp[i]);
                for (int j : adj[i]) dp[j] = max(dp[j], dp[i] + 1);
            }
            cout << res << '\n';
        }
        else
        {
            int res = -1;
            for (array<int, 2> &i : b[t])
            {
                if (!inq[i[1]]) 
                {
                    res = i[0];
                    break;
                }
            }
            cout << res << '\n';
        }
        for (int &i : v) inq[i] = 0;
    }

}
signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
    // cin >> t;
    for (int tt = 1; tt <= t; tt++)
    {
        _();
    }
}

Compilation message (stderr)

bitaro.cpp: In function 'void init(int)':
bitaro.cpp:24:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         while (nw.size() < B + 1 && i < b[a].size() && j < b[v].size())
      |                                     ~~^~~~~~~~~~~~~
bitaro.cpp:24:58: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         while (nw.size() < B + 1 && i < b[a].size() && j < b[v].size())
      |                                                        ~~^~~~~~~~~~~~~
bitaro.cpp:39:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |         while (nw.size() < B + 1 && i < b[a].size()) if (in[b[a][i][1]] && ++i) continue; else nw.push_back(b[a][i]), in[b[a][i++][1]] = 1;
      |                                     ~~^~~~~~~~~~~~~
bitaro.cpp:40:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |         while (nw.size() < B + 1 && j < b[v].size()) if (in[b[v][j][1]] && ++j) continue; else nw.push_back({b[v][j][0] + 1, b[v][j][1]}), in[b[v][j++][1]] = 1;
      |                                     ~~^~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 86 / 86