Submission #489791

#	Time	Username	Problem	Language	Result	Execution time	Memory
489791		BackNoob	Bitaro’s Party (JOI18_bitaro)	C++14	100 / 100	1891 ms	439736 KiB

bitaro

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define endl '\n'
#define MASK(i) (1LL << (i))
#define ull unsigned long long
#define ld long double
#define pb push_back
#define all(x) (x).begin() , (x).end()
#define BIT(x , i) ((x >> (i)) & 1) 
#define TASK "task"
#define sz(s) (int) (s).size()

using namespace std;
const int mxN = 3e5 + 227;
const int inf = 1e9 + 277;
const int mod = 1e9 + 7;
const ll infll = 1e18 + 7;
const int base = 307;
const int LOG = 20;
const int SQ = 320;
 
template <typename T1, typename T2> bool minimize(T1 &a, T2 b) {
	if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maximize(T1 &a, T2 b) {
	if (a < b) {a = b; return true;} return false;
}

vector<int> topo;
vector<int> adj[mxN];
vector<int> radj[mxN];
bool vis[mxN];
bool isremove[mxN];
int dp[mxN];

void dfs(int u)
{
	vis[u] = true;
	for(int v : adj[u]) {
		if(!vis[v]) dfs(v);
	}
	topo.pb(u);
}

vector<pair<int , int>> best[mxN];
bool have[mxN];

vector<pair<int , int>> modify(vector<pair<int , int>> a , vector<pair<int , int>> b)
{
	vector<pair<int , int>> res;

	int lef = 0;
	int rig = 0;

	while(sz(res) < SQ &&  (lef < sz(a) || rig < sz(b))) {
		if(lef == sz(a)) {
			if(have[b[rig].fi] == false) {
				have[b[rig].fi] = true;
				res.pb(b[rig]);
			}
			rig++;
		}
		else {
			if(rig == sz(b)) {
				if(have[a[lef].fi] == false) {
					have[a[lef].fi] = true;
					res.pb(a[lef]);
				}
				lef++;
			}
			else {
				if(a[lef].se < b[rig].se) {
					if(have[b[rig].fi] == false) {
						have[b[rig].fi] = true;
						res.pb(b[rig]);
					}
					rig++;
				}
				else {
					if(have[a[lef].fi] == false) {
						have[a[lef].fi] = true;
						res.pb(a[lef]);
					}
					lef++;
				}
			}
		}
	}

	for(auto it : res) have[it.fi] = false;

	return res;
}

void calc(int u)
{
	best[u].pb({u , 0});
	vis[u] = true;

	for(int v : radj[u]) {
		if(!vis[v]) calc(v);
		vector<pair<int , int>> tmp = best[v];
		for(auto &it : tmp) it.se++;

		best[u] = modify(best[u] , tmp);
	}
}

void solve()
{
	int n , m , q;
	cin >> n >> m >> q;
	for(int i = 1 ; i <= m ; i++) {
		int u , v;
		cin >> u >> v;
		adj[u].pb(v);
		radj[v].pb(u);
	}
	
	for(int i = 1 ; i <= n ; i++) if(!vis[i]) dfs(i);
	reverse(all(topo));
	
	memset(vis , false , sizeof(vis));		
	for(int i = 1 ; i <= n ; i++) if(!vis[i]) calc(i);
	// for(int i : topo) cout << i << ' ';
	// cout << endl;

	while(q--) {
		int pos , x;
		cin >> pos >> x;

		vector<int> remove;
		for(int i = 1 ; i <= x ; i++) {
			int y;
			cin >> y;
			isremove[y] = true;
			remove.pb(y);
		}

		if(x >= SQ) {
			for(int i = 1 ; i <= n ; i++) dp[i] = -inf;
			for(int i : topo) {
				if(isremove[i] == false) dp[i] = 0;
				for(int j : radj[i]) {
					maximize(dp[i] , dp[j] + 1);
				}
			}

			if(dp[pos] < 0) cout << -1 << endl;
			else cout << dp[pos] << endl;
		}
		else {
			int ans = -1;
			for(auto it : best[pos]) {
				if(isremove[it.fi] == false) {
					ans = it.se;
					break;
				}
			}
			cout << ans << endl;
		}
		for(int i : remove) isremove[i] = false;
	}
}	
 
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    //freopen(TASK".in" , "r" , stdin);
    //freopen(TASK".out" , "w" , stdout);
    
    int tc = 1;
    //cin >> tc;
    while(tc--) {
    	solve();
    }
    return 0;
}

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