Submission #47761

#	Time	Username	Problem	Language	Result	Execution time	Memory
47761		mirbek01	Bitaro’s Party (JOI18_bitaro)	C++17	0 / 100	7 ms	6264 KiB

bitaro

# include <bits/stdc++.h>

using namespace std;

const int N = 1e5 + 2;

int n, m, q, d[N], used[N], ans, vis[N], f[N], t;
vector <int> g[N], gr[N];

void dfs(int v){
      if(v == t)
            return ;
      vis[v] = 1;
      for(int to : g[v]){
            if(!vis[to]){
                  dfs(to);
            }
            if(f[to]){
                  d[v] = max(d[v], d[to] + 1);
                  f[v] = 1;
            }
      }
      if(!used[v] && f[v])
            ans = max(ans, d[v]);
}

int main(){
      cin >> n >> m >> q;

      for(int i = 0; i < m; i ++){
            int u, v;
            scanf("%d %d", &u, &v);
            g[u].push_back(v);
      }

      while(q --){
            int y;
            cin >> t >> y;
            vector <int> v;
            for(int i = 1; i <= y; i ++){
                  int x;
                  scanf("%d", &x);
                  used[x] = 1;
                  v.push_back(x);
            }

            memset(d, 0, sizeof(d));
            memset(vis, 0, sizeof(vis));
            memset(f, 0, sizeof(f));
            f[t] = 1;
            ans = -1;

            for(int i = 1; i <= n; i ++){
                  if(!vis[i])
                        dfs(i);
            }

            cout << ans << endl;

            for(int i : v)
                  used[i] = 0;
      }
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:32:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d %d", &u, &v);
             ~~~~~^~~~~~~~~~~~~~~~~
bitaro.cpp:42:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
                   scanf("%d", &x);
                   ~~~~~^~~~~~~~~~

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