Submission #211936

#	Time	Username	Problem	Language	Result	Execution time	Memory
211936		godwind	Making Friends on Joitter is Fun (JOI20_joitter2)	C++14	0 / 100	15 ms	16896 KiB

joitter2

// O O O O O O O O O O O O O O O OO O OO O OO O O O TTCH O TTTCH O TTTCH O O O O
#pragma GCC optimize("Ofast")
#pragma GCC optimize("no-stack-protector")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("fast-math")
#pragma GCC target("sse,sse2,sse3,ssse3,popcnt,abm,mmx")
#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <stdio.h>
#include <cstdio>
#include <math.h>
#include <cmath>
#include <string>
#include <cstring>
#include <queue>
#include <deque>
// #include <random>
#include <iomanip>
#include <bitset>
#include <cassert>
 
using namespace std;

#define int long long
#define y1 y11
#define double long double
#define less less228
#define left left228
#define right right228
#define list list228
#define all(v) v.begin(), v.end()
 
 
 
template<typename T> void uin(T &a, T b) {
    if (b < a) a = b;
}
template<typename T> void uax(T &a, T b) {
    if (b > a) a = b;
}

const int N = 100 * 1000 + 228;

int p[N], sz[N];
vector<int> in[N];

void init(int n) {
	for (int i = 1; i <= n; ++i) {
		p[i] = i;
		sz[i] = 1;
		in[i].emplace_back(i);
	}
}
int getp(int v){
	if(v==p[v])return v;
	p[v]=getp(p[v]);
	return p[v];
}
int n,m;
int ans = 0;
map< pair<int,int>, bool> vc, is;
map< pair<int,int>,int> between;
set<int> vic[N], iic[N], outc[N];

void squeeze(int c1, int c2) {
	ans -= between[{c1, c2}] * sz[c2];
	ans -= between[{c2, c1}] * sz[c1];
	ans += 2LL * sz[c1] * sz[c2];
	if (sz[c1] > sz[c2]) swap(c1, c2);
	for (int x : in[c1]) {
		if (vic[c2].find(x) != vic[c2].end()) {
			vic[c2].erase(x);
		}
	}
	ans -= (int)vic[c2].size() * sz[c2];
	for (int x : vic[c1]) {
		if (vic[c2].find(x) != vic[c2].end()) vic[c2].erase(x);
		if (getp(x) == c2) continue;
		ans -= sz[c1];
		if (!vc[{x, c2}]) {
			vc[{x, c2}] = 1;
			vic[c2].insert(x);
		}
	}
	ans += (int)vic[c2].size() * (sz[c1] + sz[c2]);
	vector<int>suspicion;
	for (int c : iic[c1]) {
		if (getp(c) == c2) continue;
		if (!is[{c, c2}]) {
			is[{c, c2}] = 1;
			iic[c2].insert(c);
			between[{c, c2}] += between[{c, c1}];
			suspicion.emplace_back(c);
		}
	}
	for (int c : outc[c1]) {
		if (getp(c) == c2) continue;
		if (!is[{c2, c}]) {
			is[{c2, c}] = 1;
			outc[c2].insert(c);
			between[{c2, c}] += between[{c1, c}];
			suspicion.emplace_back(c);
		}
	}
	for (int x : in[c1]) {
		if (outc[c2].find(x) != outc[c2].end()) {
			outc[c2].erase(x);
		}
	}
	p[c1] = c2;
	sz[c2] += sz[c1];
	for (int x : in[c1]) {
		in[c2].emplace_back(x);
	}
	for (int c : suspicion) {
		if (is[{getp(c2), getp(c)}] && is[{getp(c), getp(c2)}]) {
			squeeze(getp(c), getp(c2));
		}
	}

}

void add(int a, int b) {
	int c1 = getp(a);
	int c2 = getp(b);
	if (c1 == c2)return;
	// c1 --> c2
	if (!is[{c2, c1}]) {
		is[{c1, c2}] = 1;
		iic[c2].insert(c1);
		outc[c1].insert(c2);
		if (!vc[{a, c2}]) {
			++between[{c1, c2}];
			ans += sz[c2];
			vc[{a, c2}] = 1;
			vic[c2].insert(a);
		}
	} else {
		squeeze(c1, c2);
	}
}


signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    init(n);
    for (int i = 0; i < m; ++i) {
    	int u, v;
    	cin >> u >> v;
    	add(u, v);
    	cout << ans << '\n';
    }
    return 0;
}
// RU_023
 
/*
4 6
1 2
2 3
3 2
1 3
3 4
4 3

*/

• Subtask 1: 0 / 1
• Subtask 2: 0 / 16
• Subtask 3: 0 / 83