제출 #1134172

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1134172		Zbyszek99	조이터에서 친구를 만드는건 재밌어 (JOI20_joitter2)	C++20	0 / 100	6 ms	12096 KiB

joitter2

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e8+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;

vi comp[100001];
int rep_[100001];
int siz_[100001];

set<pii> in_v[100001];
set<pii> out_v[100001];

set<pii> comp_edges;
set<pii> comp_edges_rev;


vector<pii> list_to_union;

ll cur_ans = 0;

int fint(int v)
{
    if(rep_[v] == v) return v;
    rep_[v] = fint(rep_[v]);
    return rep_[v];
}

set<int> in_del;

bool check(int a, int b)
{
    a = fint(a);
    b = fint(b);
    return a != b && comp_edges.find({a,b}) != comp_edges.end() && comp_edges.find({b,a}) != comp_edges.end();
}

void onion(int a, int b)
{
    if(siz_[a] > siz_[b]) swap(a,b);
    cur_ans -= (ll)(siz_[a]) * (ll)(siz_[a]-1);
    cur_ans -= (ll)(siz_[b]) * (ll)(siz_[b]-1);
    
    cur_ans -= (ll)siz(in_v[a]) * (ll)siz_[a];
    cur_ans -= (ll)siz(in_v[b]) * (ll)siz_[b];
    vector<pii> del;
    //cout << (ll)siz(in_v[a]) << " " << (ll)siz(in_v[b]) << " " << a << " " << b << " ic\n";
    forall(it,in_v[a])
    {
        if(fint(it.ff) == b)
        {
            out_v[b].erase(out_v[b].find({it.ss,it.ff}));
            del.pb(it);
        }
    }
    forall(it,del)
    {
        in_v[a].erase(in_v[a].find(it));
    }
    del = {};
    forall(it,out_v[a])
    {
        if(fint(it.ff) == b)
        {
            in_v[b].erase(in_v[b].find({it.ss,it.ff}));
            del.pb(it);
        }
    }
    forall(it,del)
    {
        out_v[a].erase(out_v[a].find(it));
    }
    del = {};
   // cout << "xd\n";
    auto it = comp_edges.lower_bound({a,-1});
    while(it != comp_edges.end() && (*it).ff == a)
    {
        int p1 = a;
        int p2 = (*it).ss;
      //  cout << p1 << " " << p2 << " comp\n";
        it++;
        comp_edges.erase(comp_edges.find({p1,p2}));
        comp_edges_rev.erase(comp_edges_rev.find({p2,p1}));
        if(b != p2)
        {
            comp_edges.insert({b,p2});
            comp_edges_rev.insert({p2,b});
            if(check(b,p2)) list_to_union.pb({b,p2});
        }
    }
    it = comp_edges_rev.lower_bound({a,-1});
    while(it != comp_edges_rev.end() && (*it).ff == a)
    {
        int p1 = a;
        int p2 = (*it).ss;
       // cout << p1 << " " << p2 << " comp2\n";
        it++;
        comp_edges.erase(comp_edges.find({p2,p1}));
        comp_edges_rev.erase(comp_edges_rev.find({p1,p2}));
        if(b != p2)
        {
            comp_edges.insert({p2,b});
            comp_edges_rev.insert({b,p2});
            if(check(b,p2)) list_to_union.pb({b,p2});
        }
    }
    forall(it,in_v[a]) in_v[b].insert(it);
    forall(it,out_v[a]) out_v[b].insert(it);
    rep_[a] = b;
    siz_[b] += siz_[a];
    cur_ans += (ll)(siz_[b]) * (ll)(siz_[b]-1);
    cur_ans += (ll)siz(in_v[b]) * (ll)siz_[b];
    //cout << a << " " << b << " " << (ll)siz(in_v[b]) << " " << siz_[b] << " res\n"; 
}

void try_union()
{
    while(!list_to_union.empty())
    {
        pii w = list_to_union.back();
        list_to_union.pop_back();
        int a = fint(w.ff);
        int b = fint(w.ss);
        if(a == b) continue;
        onion(a,b);
    }
}

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //random_start();
    int n,m;
    cin >> n >> m;
    rep2(i,1,n)
    {
        rep_[i] = i;
        siz_[i] = 1; 
        comp[i] = {i};
    }
    rep(i,m)
    {
        int a,b;
        cin >> a >> b;
        int a2 = a;
        int b2 = b;
        a = fint(a);
        b = fint(b);
        if(a == b) 
        {
            cout << cur_ans << "\n";
            continue;
        }
        auto it = in_v[b].lower_bound({a2,-1});
        if(it == in_v[b].end() || (*it).ff != a)
        {
            in_v[b].insert({a2,b2});
            out_v[a].insert({b2,a2});
            cur_ans += siz_[b];
            comp_edges.insert({a,b});
            comp_edges_rev.insert({b,a});
        }
        if(check(a,b))
        {
            list_to_union.pb({a,b});
        }
        try_union();
        cout << cur_ans << "\n";
    }
}

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