Submission #1193002

#	Time	Username	Problem	Language	Result	Execution time	Memory
1193002		thelegendary08	Making Friends on Joitter is Fun (JOI20_joitter2)	C++17	100 / 100	520 ms	75324 KiB

joitter2

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define pout(a) cout<<a.first<<' '<<a.second<<'\n'
#define vout(v) cout<<#v<<' '; for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
const int mxn = 1e5 + 5;
vi par(mxn), sz(mxn), cont(mxn);
vector<set<int>> in(mxn), out(mxn), in_nodes(mxn), s(mxn);
int ans = 0;
queue<pii>q;
int find(int x){
	while(x != par[x])x = par[x];
	return x;
}

void merge(int a, int b){
	// out2(a,b);
	a = find(a); b = find(b);
	if(a == b)return;
	if(sz[a] < sz[b]){
		swap(a,b);
	}
	
	sz[a] += sz[b];
	par[b] = a;
	ans -= cont[a]; ans -= cont[b]; 
	for(auto u : s[b]){
		s[a].insert(u);
		in_nodes[a].erase(u);
	}
	for(auto u : in_nodes[b]){
		if(!s[a].count(u))in_nodes[a].insert(u);
	}
	in[a].erase(b);
	out[a].erase(b);
	for(auto u : in[b]){
		if(u != a){
			in[a].insert(u);
			out[u].erase(b);
			out[u].insert(a);
			if(out[a].count(u)){
				q.push(mp(u, a));
			}
		}
	}
	for(auto u : out[b]){
		if(u != a){
			out[a].insert(u);
			in[u].erase(b);
			in[u].insert(a);
			if(in[a].count(u)){
				q.push(mp(u,a));
			}
		}
	}
	
	// vout(s[a]);
	// vout(in[a]);
	// vout(out[a]);
	cont[a] = (s[a].size() - 1) * s[a].size() + s[a].size() * in_nodes[a].size();
	
	ans += cont[a];
}

void bfs(){
	while(!q.empty()){
		pii node = q.front();
		q.pop();
		merge(node.first, node.second);
	}
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	in2(n,m);
	f0r(i,n){
		par[i] = i;
		sz[i] = 1;
		s[i].insert(i);
	}
	f0r(i,m){
		in2(a,b);
		a--; b--;
		int ca = find(a);
		int cb = find(b);
		if(ca == cb){}
		else if(in_nodes[cb].count(a)){}
		else if(out[cb].count(ca)){
			q.push(mp(ca, cb));
			bfs();
		}
		else{
			in_nodes[cb].insert(a);
			in[cb].insert(ca);
			out[ca].insert(cb);
			cont[cb] += sz[cb];
			ans += sz[cb];
		}
		
		cout<<ans<<'\n';
	}
}

• Subtask 1: 1 / 1
• Subtask 2: 16 / 16
• Subtask 3: 83 / 83