Submission #1354661

#	Time	Username	Problem	Language	Result	Execution time	Memory
1354661		kokokai	Bitaro’s Party (JOI18_bitaro)	C++20	14 / 100	491 ms	417044 KiB

bitaro

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define fi first
#define se second
#define task "text"
const int N = 1e5+4;

vector<int> adj[N];
int n,m,q;
vector<pair<int,int>> vers[N];
int dist[N],used[N];
vector<int> from[N];
int mxd[N];
bool has[N];
int main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);
    if(fopen(task".inp","r")){
        freopen(task".inp","r",stdin);
    }
    cin>>n>>m>>q;
    int can=299;
    for(int i=1;i<=m;i++){
        int u,v;
        cin>>u>>v;
        adj[v].push_back(u);
    }
    for(int i=1;i<=n;i++){
        dist[i]=0;
        vector<int> ver;
        ver.push_back(i);
        for(int v:adj[i]){
            mxd[i]=max(mxd[i],mxd[v]+1);
            for(pair<int,int> x:vers[v]){
                dist[x.se]=max(dist[x.se],x.fi+1);
                ver.push_back(x.se);
            }
        }
        for(int v:ver){
            if(!used[v]){
                used[v]=1;
                from[dist[v]].push_back(v);
            }
        }
        int cnt=0;
        for(int d=mxd[i];d>=max(0,mxd[i]-can);d--){
            int j=0;
            while(cnt<can && j<from[d].size()){
                vers[i].push_back({d,from[d][j]});
                j++;
                cnt++;
            }
        }
        for(int v:ver){
            from[dist[v]].clear();
            used[v]=0;
            dist[v]=0;
        }
    }
    memset(dist,0,sizeof dist);
    while(q--){
        int u,y;
        cin>>u>>y;
        vector<int> ver;
        for(int i=1;i<=y;i++){
            int x;
            cin>>x;
            ver.push_back(x);
            has[x]=1;
        }
        int ans=-1;
        if(y < can){
            for(int i=vers[u].size()-1;i>=0;i--){
                if(!has[vers[u][i].se]){
                    ans=vers[u][i].fi;
                    break;
                }
            }
            cout<<ans<<'\n';
            for(int v:ver) has[v]=0;
        }else{
            //cerr<<2<<'\n';
            for(int i=1;i<=n;i++){
                if(has[i]){
                    dist[i]=-1;
                }
                else dist[i]=0;
                for(int v:adj[i]){
                    if(dist[v]>=0){
                        dist[i]=max(dist[i],dist[v]+1);
                    }
                }
            }
            cout<<dist[u]<<'\n';
            for(int v:ver) has[v]=0;
            for(int i=1;i<=n;i++) dist[i]=0;
        }
    }
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:19:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |         freopen(task".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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