Submission #399357

#	Time	Username	Problem	Language	Result	Execution time	Memory
399357		knightron0	Bitaro’s Party (JOI18_bitaro)	C++17	14 / 100	1385 ms	419616 KiB

bitaro

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

#define pb push_back
#define fr first
#define sc second
#define clr(a, x) memset(a, x, sizeof(a))
#define dbg(x) cout<<"("<<#x<<"): "<<x<<endl;
#define printvector(arr) for (auto it = arr.begin(); it != arr.end(); ++it) cout<<*it<<" "; cout<<endl;
#define all(v) v.begin(), v.end()
#define lcm(a, b) (a * b)/__gcd(a, b)
// #define int long long int
#define printvecpairs(vec) for(auto it: vec) cout<<it.fr<<' '<<it.sc<<endl;
#define endl '\n'
#define float long double

const int INF = 1e8;
const int MOD = 1e9 + 7;
const int MAXN = 1e5 + 5;
const int B = 315;

vector<int> adj[MAXN], rev[MAXN];
int dist[MAXN];
bool notok[MAXN];
vector<pair<int, int>> f[MAXN];

bool cmp(int x, int y){ 
	return dist[x] > dist[y]; 
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    #endif
    int n, m, q;
    cin>>n>>m>>q;
    for(int i= 0;i<m;i++){
    	int u, v;
    	cin>>u>>v;
    	adj[u].pb(v);
    	rev[v].pb(u);
    }
    clr(dist, 0);
    bool done[n+2];
    clr(done, 0);
    for(int i=1;i<=n;i++){
    	vector<int> s;
    	s.pb(i);
    	for(int v: rev[i]){
    		for(auto it: f[v]){
    			if(!done[it.sc]){
    				s.pb(it.sc);
    				done[it.sc] = 1;
    			}
    			dist[it.sc] = max(it.fr+1, dist[it.sc]);
    		}
    	}
    	// printvector(s);
    	int ln = min((int)s.size()-1, B);
    	nth_element(s.begin(), s.begin()+ln, s.end(), cmp);
    	// printvector(s);
    	int curr = 0;
    	for(int u: s){
    		if(curr >= B){
    			break;
    		}
    		f[i].pb({dist[u], u});
    		curr++;
    	}
    	for(auto it: s){
    		dist[it] = 0;
    		done[it] = 0;
    	}
    }
    clr(notok, 0);
   	while(q--){
   		int x, y; cin>>x>>y;
   		vector<int> v;
   		for(int i= 0;i<y;i++){
   			int t1; cin>>t1;
   			v.pb(t1);
   			notok[t1] =1;
   		}
   		if(y >= B){
   			int dp[n+2], ans = -1;   			
  			for(int i=1;i<=n;i++) dp[i] = -INF;
   			dp[x] = 0;
   			for(int i= x;i>=1;i--){
   				for(int v: adj[i]){
   					dp[i] = max(dp[v]+1, dp[i]);
   				}
   				if(notok[i]) continue;
   				ans = max(ans, dp[i]);
   			}
   			cout<<ans<<endl;
   		} else {
   			int ans = -1;
   			for(auto &[d, u]: f[x]){
   				if(notok[u]) continue;
   				ans = d;
   				break;
   			}
   			cout<<ans<<endl;
   		}
   		for(int i: v){
   			notok[i] = 0;
   		}
   	} 
    return 0;
}

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