Submission #259760

#	Time	Username	Problem	Language	Result	Execution time	Memory
259760		amoo_safar	Making Friends on Joitter is Fun (JOI20_joitter2)	C++17	100 / 100	1430 ms	67708 KiB

joitter2

// Zende bad Shoma nasime faghat !
#include <bits/stdc++.h>

#define pb push_back
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " : " << x << '\n'

using namespace std;

typedef long long ll;
typedef long double ld;
typedef string str;
typedef pair<ll, ll> pll;

const ll Mod = 1000000007LL;
const int N = 1e5 + 10;
const ll Inf = 2242545357980376863LL;
const ll Log = 30;

ll ans;
int n, m;

set<int> I[N], O[N];

int par[N], sz[N];
set<int> st[N];

vector<pll> U;


ll Calc(int com){
	ll res = 0;
	res = 1ll * sz[com] * st[com].size();
	res -= sz[com];
	return res;
}

int Find(int u){
	if(par[u] == u) return u;
	return par[u] = Find(par[u]);
}

void AddE(int u, int v){
	v = Find(v);
	ans -= Calc(v);
	st[v].insert(u);
	ans += Calc(v);

	u = Find(u); v = Find(v);
	
	O[u].insert(v);
	I[v].insert(u);
	
	if(I[u].count(v)){
		U.pb({u, v});
	}
}
void Unite(int u, int v){
	u = Find(u); v = Find(v);
	if(u == v) return ;
	if(sz[u] > sz[v]) swap(u, v);
	
	ans -= Calc(u); ans -= Calc(v);
	for(auto x : st[u]){
		//AddE(x, v);
		st[v].insert(x);
	}
	for(auto x : I[u]){
		if(O[v].count(x)){
			U.pb({v, x});
		}

		I[v].insert(x);
		
		O[x].erase(u);
		O[x].insert(v);
	}

	for(auto x : O[u]){
		
		if(I[v].count(x)){
			U.pb({v, x});
		}

		O[v].insert(x);
		
		I[x].erase(u);
		I[x].insert(v);
	}

	st[u].clear(); I[u].clear(); O[u].clear();
	//st[u].shrink_to_fit();

	par[u] = v;
	sz[v] += sz[u];
	ans += Calc(v);
}

int main(){
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	iota(par, par + N, 0);
	fill(sz, sz + N, 1);
	cin >> n >> m;
	for(int i = 1; i <= n; i++) st[i].insert(i);

	int u, v;
	for(int i = 0; i < m; i++){
		cin >> u >> v;
		AddE(u, v);
		int f1, f2;
		while(!U.empty()){
			f1 = U.back().F; f2 = U.back().S;
			U.pop_back();
			Unite(f1, f2);
			//cerr << "# " << f1 << ' ' << f2 << '\n';
		}
		cout << ans << '\n';
	}
	return 0;
}
/*
4 6
1 2
2 1
3 4
4 3
1 3
4 2


8 14
1 2
2 1

3 4
4 5
5 4
4 3

6 7
7 8
8 7
7 6

1 3
4 7
6 1

8 5

*/

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