Submission #985665

#	Time	Username	Problem	Language	Result	Execution time	Memory
985665		SmuggingSpun	Bitaro’s Party (JOI18_bitaro)	C++14	14 / 100	94 ms	13576 KiB

bitaro

#include<bits/stdc++.h>
#define taskname "A"
using namespace std;
const int INF = 1e9;
template<class T>void maximize(T& a, T b){
	if(a < b){
		a = b;
	}
}
int n, m, q;
namespace sub12{
	const int lim = 1e5 + 5;
	vector<int>e[lim];
	int dp[lim];
	void solve(){
		for(int _ = 0; _ < m; _++){
			int u, v;
			cin >> u >> v;
			e[v].emplace_back(u);
		}
		int t, y;
		cin >> t >> y;
		bitset<lim>busy;
		busy.reset();
		for(int _ = 0; _ < y; _++){
			int x;
			cin >> x;
			busy.set(x);
		}
		for(int i = 1; i <= n; i++){
			dp[i] = (busy.test(i) ? -INF : 0);
			for(int& v : e[i]){
				maximize(dp[i], dp[v] + 1);
			}
		}
		cout << max(dp[t], -1);
	}
}
namespace sub3{
	const int lim = 1e5 + 5;
	vector<int>e[lim];
	int deg[lim], dp[lim], f[lim];
	bitset<lim>busy;
	void work(int index){
		busy.reset(index);
		f[index] = 0;
		for(int& x : e[index]){
			if(!busy.test(x)){
				maximize(f[index], f[x] + 1);
				break;
			}
			work(x);
			maximize(f[index], f[x] + 1);
		}
	}
	void solve(){
		for(int _ = 0; _ < m; _++){
			int u, v;
			cin >> u >> v;
			e[v].emplace_back(u);
		}
		memset(dp, 0, sizeof(dp));
		for(int i = 1; i <= n; i++){
			sort(e[i].begin(), e[i].end(), [&] (int i, int j) -> bool{
				return dp[i] > dp[j];
			});
			if(!e[i].empty()){
				dp[i] = dp[e[i][0]] + 1;
			}
			f[i] = dp[i];
		}
		busy.reset();
		for(int _ = 0; _ < q; _++){
			int t, y;
			cin >> t >> y;
			vector<int>a(y);
			for(int& x : a){
				cin >> x;
				busy.set(x);
			}
			work(t);
			cout << f[t] << "\n";
			for(int& x : a){
				busy.reset(x);
				f[x] = dp[x];
			}
			f[t] = dp[t];
		}
	}
}
int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	if(fopen(taskname".inp", "r")){
		freopen(taskname".inp", "r", stdin);
	}
	cin >> n >> m >> q;
	if(q == 1){
		sub12::solve();
	}
	else{
		sub3::solve();
	}
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:94:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   94 |   freopen(taskname".inp", "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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