Submission #211975

#	Time	Username	Problem	Language	Result	Execution time	Memory
211975		godwind	Making Friends on Joitter is Fun (JOI20_joitter2)	C++14	0 / 100	13 ms	12160 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> is;
map< pair<int,int>,int> between;
set<int> vic[N], vouc[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);
            vouc[x].erase(c2);
        }
    }
    int izn = (int)vic[c2].size();
    vector<int> suspicion;
    int cnt = 0;
    for (int x : vic[c1]) {
        if (getp(x) == c2) continue;
        if (!vic[c2].count(x)) {
            vic[c2].insert(x);
            vouc[x].insert(c2);
            ans += sz[c2];
            ++between[{getp(x), c2}];
            suspicion.emplace_back(getp(x));
        } else ++cnt;
        is[{getp(x), c2}] = 1;
    }
    ans += (izn - cnt) * sz[c1];
    for (int x : in[c1]) {
        for (auto y : vouc[x]) {
            if (getp(y) == c2 || getp(y) == c1) continue;
            ++between[{c2, getp(y)}];
            is[{c2, getp(y)}] = 1;
            suspicion.emplace_back(getp(y));
        }
    }
    p[c1] = c2;
    sz[c2] += sz[c1];
    for (int x : in[c1]) {
        in[c2].emplace_back(x);
    }
    for (int c : suspicion) {
        if (c != c2 && c != c1 && 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;
        if (!vic[c2].count(a)) {
            ++between[{c1, c2}];
            ans += sz[c2];
            vic[c2].insert(a);
            vouc[a].insert(c2);
        }
    } 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

4 6
3 1
4 1
2 4
2 1
1 4
1 2
(9)

*/

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