Submission #820059

#	Time	Username	Problem	Language	Result	Execution time	Memory
820059		smirichto	Bitaro’s Party (JOI18_bitaro)	C++17	0 / 100	2074 ms	5972 KiB

bitaro

#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef long double ld;
#define pb push_back
#define pi pair<ll,ll>
#define F first
#define S second
#define all(x) (x).begin(), (x).end()
#define alll(x) ((x).begin()+1), (x).end()
#define clean(v) (v).resize(distance((v).begin(), unique(all(v))));
#define yes cout<<"Yes"<<endl;
#define no cout<<"No"<<endl;
#define mod mod
#define endl '\n'
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll mod = 998244353;

void io() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);
}

template<class T>
bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }

template<class T>
bool ckmin(T &a, const T &b) { return a > b ? a = b, 1 : 0; }

void nop() {
    cout << -1 << endl;
    return;
}

const int N = 1e5+5 , B = 350 ;
vector<int> adj[N] ;
vector<pi> best[N] ;

vector<pi> merge(vector<pi> a , vector<pi> b)
{
    vector<pi> tmp  ;
    for(auto p : b) a.pb({p.F+1 , p.S}) ;
    sort(all(a)) ; reverse(all(a)) ;
    map<int,int> vis ;
    for(auto p : a){
        if(vis[p.S]) continue;
        vis[p.S] = 1 ;
        tmp.pb(p) ;
        if(tmp.size()>B+3) break ;
    }
    return tmp ;


}

map<int,int> marked ;
int ans ;

void work(int t , int dep)
{
    if(!marked[t]) ckmax(ans , dep) ;
    for(int to : adj[t]) work(to , dep+1) ;
}

void solve() {
    int n , m , q ;
    cin>>n>>m>>q ;
    for(int i = 1 ; i<=m ; i++){
        int u , v ;
        cin>>u>>v ;
        adj[v].pb(u) ;
    }
    for(int i = 1 ; i<=n ; i++){
        best[i].pb({0 , i}) ;
        for(int to  : adj[i]){
            best[i] = merge(best[i] , best[to]) ;
        }
    }
    while(q--){
        int t , y ;
        cin>>t>>y ;
        marked.clear() ;
        for(int i = 1 ; i<=y ; i++){
            int x ; cin>>x ;
            marked[x] = 1 ;
        }
        ans = -1 ;
        if(y<=B){
            for(int i = 0 ; i<best[t].size() ; i++){
                if(!marked[best[t][i].S]){
                    ans = best[t][i].F ;
                    break ;
                }
            }
        }
        else{
            work(t , 0) ;
        }
        cout<<ans<<endl;

    }

}

int main() {
#ifndef ONLINE_JUDGE
    freopen("input.in", "r", stdin);
    freopen("output.out", "w", stdout);
#endif
    io();
    ll tt = 1;
    //cin>>tt ;
    while (tt--) {
        solve();
    }

    return 0;
}

Compilation message (stderr)

bitaro.cpp: In function 'void solve()':
bitaro.cpp:90:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   90 |             for(int i = 0 ; i<best[t].size() ; i++){
      |                             ~^~~~~~~~~~~~~~~
bitaro.cpp: In function 'int main()':
bitaro.cpp:108:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  108 |     freopen("input.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
bitaro.cpp:109:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  109 |     freopen("output.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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