제출 #226191

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
226191		Minnakhmetov	조이터에서 친구를 만드는건 재밌어 (JOI20_joitter2)	C++14	0 / 100	5 ms	512 KiB

joitter2

#include <bits/stdc++.h>
using namespace std;
 
#define ll long long
#define all(aaa) aaa.begin(), aaa.end()

const int N = 1e5 + 5;
int w[N];
set<int> *members[N], *ingoing_ver[N], *outgoing_gr[N], *ingoing_gr[N];
ll ans = 0;
int n, m;

int find_set(int x) {
    return w[x] < 0 ? x : w[x] = find_set(w[x]);
}

void mrg(int x, int y) {
    x = find_set(x);
    y = find_set(y);

    if (x == y)
        return;

    ans -= members[x]->size() * (ll)(members[x]->size() - 1);
    ans -= members[y]->size() * (ll)(members[y]->size() - 1);

    ans -= ingoing_ver[x]->size() * (ll)members[x]->size();
    ans -= ingoing_ver[y]->size() * (ll)members[y]->size();

    if (members[x]->size() + ingoing_ver[x]->size() < 
        members[y]->size() + ingoing_ver[y]->size()) {
        swap(members[x], members[y]);
        swap(ingoing_ver[x], ingoing_ver[y]);
    }

    for (const int &el : *members[y]) {
        members[x]->insert(el);
        ingoing_ver[x]->erase(el);
    }

    for (const int &el : *ingoing_ver[y]) {
        if (!members[x]->count(el)) {
            ingoing_ver[x]->insert(el);
        }
    }

    ans += ingoing_ver[x]->size() * (ll)members[x]->size();
    ans += members[x]->size() * (ll)(members[x]->size() - 1);

    if (ingoing_gr[x]->size() + outgoing_gr[x]->size() < 
        ingoing_gr[y]->size() + outgoing_gr[y]->size()) {
        swap(x, y);
        swap(members[x], members[y]);
        swap(ingoing_ver[x], ingoing_ver[y]);
    }

    ingoing_gr[y]->erase(x);
    ingoing_gr[x]->erase(y);

    for (const int &el : *ingoing_gr[y]) {
        ingoing_gr[x]->insert(el);
        outgoing_gr[el]->erase(y);
        outgoing_gr[el]->insert(x);
    }

    vector<int> to_mrg;

    outgoing_gr[y]->erase(x);
    outgoing_gr[x]->erase(y);

    for (const int &el : *outgoing_gr[y]) {
        outgoing_gr[x]->insert(el);
        ingoing_gr[el]->erase(y);
        ingoing_gr[el]->insert(x);
        if (ingoing_gr[el]->count(x) &&
            outgoing_gr[el]->count(x)) {
            to_mrg.push_back(el);
        }
    }

    w[y] = x;

    for (const int &el : to_mrg) {
        mrg(el, x);
    }
}

void add_edge(int x, int y) {
    y = find_set(y);

    if (find_set(x) == y)
        return;

    if (!ingoing_ver[y]->count(x)) {
        ans += members[y]->size();
        ingoing_ver[y]->insert(x);
    }

    x = find_set(x);

    ingoing_gr[y]->insert(x);
    outgoing_gr[x]->insert(y);

    if (outgoing_gr[y]->count(x)) {
        mrg(x, y);
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n, m;
    cin >> n >> m;

    for (int i = 0; i < n; i++) {
        w[i] = -1;
        ingoing_gr[i] = new set<int>();
        outgoing_gr[i] = new set<int>();
        ingoing_ver[i] = new set<int>();
        members[i] = new set<int>();
        members[i]->insert(i);
    }

    for (int i = 0; i < m; i++) {
        int x, y;
        cin >> x >> y;
        x--, y--;

        add_edge(x, y);

        cout << ans << "\n";
    }

    return 0;
}

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