Submission #47759

#	Time	Username	Problem	Language	Result	Execution time	Memory
47759		daniel_02	Bitaro’s Party (JOI18_bitaro)	C++17	14 / 100	2061 ms	8044 KiB

bitaro

#include <bits/stdc++.h>

#define pb push_back
#define fr first
#define sc second

using namespace std;

const int N = 1e5 + 7;
const int inf = 1e9 + 7;

priority_queue<pair<int, int>>q;
vector<pair<int, int>>g[N];
bool busy[N];
int d[N];

main()
{
    int n, m, Q;

    cin >> n >> m >> Q;

    for (int i = 1; i <= m; i ++)
    {
        int u, v;

        scanf("%d%d", &u, &v);

        g[v].pb({u, 1});
    }

    while (Q--)
    {
        int t, k, mx;

        scanf("%d%d", &t, &k);

        for (int i = 0; i < k; i++)
        {
            int a;
            scanf("%d", &a);
            busy[a] = 1;
        }
        for (int i = 1; i <= n; i++)
            d[i] = -inf;

        q.push({t, 0});
        d[t] = 0;
        while (!q.empty())
        {
            int v = q.top().fr, cs = q.top().sc * -1;
            q.pop();
            if (d[v] < cs)continue;


            for (int i = 0; i < g[v].size(); i++)
            {
                int to = g[v][i].fr, cost = g[v][i].sc;

                if (d[to] < cost + d[v])
                {
//                    cout << v << " " << to << " " << d[v] << endl;
                    d[to] = cost + d[v];
                    q.push({to, -d[v]});
                }
            }
        }
        mx = -1;

        for (int i = 1; i <= n; i++)
        {
            if (!busy[i] && d[i] != -inf)
            {
                mx = max(mx, d[i]);
            }
        }

        if (mx == -1 || mx == -inf)
        {
            cout << -1 << endl;
            continue;
        }

        cout << mx << endl;
        memset(busy, 0, sizeof(busy));
    }
}

Compilation message (stderr)

bitaro.cpp:17:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main()
      ^
bitaro.cpp: In function 'int main()':
bitaro.cpp:56:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for (int i = 0; i < g[v].size(); i++)
                             ~~^~~~~~~~~~~~~
bitaro.cpp:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &u, &v);
         ~~~~~^~~~~~~~~~~~~~~~
bitaro.cpp:36:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &t, &k);
         ~~~~~^~~~~~~~~~~~~~~~
bitaro.cpp:41:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d", &a);
             ~~~~~^~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 0 / 86