Submission #619921

#	Time	Username	Problem	Language	Result	Execution time	Memory
619921		errorgorn	Naboj (COCI22_naboj)	C++17	110 / 110	464 ms	44960 KiB

naboj

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

#define int long long
#define ll long long
#define ii pair<ll,ll>
#define fi first
#define se second
#define endl '\n'

#define puf push_front
#define pof pop_front
#define pub push_back
#define pob pop_back
#define lb lower_bound
#define ub upper_bound

#define rep(x,s,e) for (auto x=(s)-((s)>(e));x!=(e)-((s)>(e));((s)<(e)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int) (x).size()

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

int n,m;
vector<ii> al[200005];
int in[200005];
int out[200005];
bool vis[200005];

vector<int> v;
vector<ii> ans;

signed main(){
	cin.tie(0);
	cout.tie(0);
	cin.sync_with_stdio(false);
	
	cin>>n>>m;
	
	int a,b;
	rep(x,0,m){
		cin>>a>>b;
		al[a].pub({b,0});
		al[b].pub({a,1});
		
		in[b]++;
		out[a]++;
	}
	
	rep(x,1,n+1) if (in[x]==0 || out[x]==0){
		vis[x]=true;
		v.pub(x);
	}
	
	while (!v.empty()){
		int u=v.back(); v.pob();
		
		if (in[u]==0) ans.pub({u,1});
		else ans.pub({u,0});
		
		for (auto [it,x]:al[u]){
			if (!vis[it]){
				if (x==0) in[it]--;
				else out[it]--;
				
				if (in[it]==0 || out[it]==0){
					vis[it]=true;
					v.pub(it);
				}
			}
		}
	}
	
	reverse(all(ans));
	
	if (sz(ans)==n){
		cout<<sz(ans)<<endl;
		for (auto [a,b]:ans) cout<<a<<" "<<b<<endl;
	}
	else{
		cout<<"-1"<<endl;
	}
	
}

• Subtask 1: 15 / 15
• Subtask 2: 25 / 25
• Subtask 3: 70 / 70