Submission #918486

#	Time	Username	Problem	Language	Result	Execution time	Memory
918486		trMatherz	Making Friends on Joitter is Fun (JOI20_joitter2)	C++17	0 / 100	1 ms	344 KiB

joitter2

#include <iostream> //cin, cout

/*
#include <fstream>
std::ifstream cin ("ex.in");
std::ofstream cout ("ex.out");
*/




// includes
#include <cmath> 
#include <set>
#include <map>
#include <queue>
#include <string>
#include <vector>
#include <array>
#include <algorithm>
#include <numeric>
#include <iomanip>
#include <unordered_set>
#include <stack>
#include <ext/pb_ds/assoc_container.hpp>
#include <random>
#include <chrono>



//usings 
using namespace std;
using namespace __gnu_pbds;


// misc
#define ll long long
#define pb push_back
#define pq priority_queue
#define ub upper_bound
#define lb lower_bound
template<typename T, typename U> bool emin(T &a, const U &b){ return b < a ? a = b, true : false; }
template<typename T, typename U> bool emax(T &a, const U &b){ return b > a ? a = b, true : false; }
typedef uint64_t hash_t;

// vectors
#define vi vector<int>
#define vvi vector<vi>
#define vvvi vector<vvi>
#define vpii vector<pair<int, int>>
#define vvpii vector<vector<pair<int, int>>>
#define vppipi vector<pair<int, pair<int, int>>>
#define vl vector<ll>
#define vvl vector<vl>
#define vvvl vector<vvl>
#define vpll vector<pair<ll, ll>>
#define vb vector<bool>
#define vvb vector<vb>
#define vs vector<string>
#define sz(x) (int)x.size()
#define rz resize
#define all(x) x.begin(), x.end()


// pairs
#define pii pair<int, int>
#define pll pair<ll, ll>
#define mp make_pair
#define f first
#define s second

// sets
#define si set<int>
#define sl set<ll>
#define ss set<string>
#define in insert
template <class T> using iset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

// maps
#define mii map<int, int>
#define mll map<ll, ll>

// loops
#define FR(x, z, y) for (int x = z; x < y; x++)
#define FRE(x, z, y) FR(x, z, y + 1)
#define F(x, y) FR(x, 0, y)
#define FE(x, y) F(x, y + 1)
#define A(x, y) for(auto &x : y)

ll an = 0;
vi dsu;
vector<set<int>> c, g, rg;
queue<pii> todo;

void weak(int x, int y){
    g[x].in(y); rg[x].in(y);
    if(g[y].find(x) != g[y].end()) todo.push({x, y});
}

int get(int x){return dsu[x] < 0 ? x : dsu[x] = get(dsu[x]);}

void merge(int x, int y){
    x = get(x), y = get(y);
    if(x == y) return;

    if(dsu[y] < dsu[x]) swap(x, y);

    an += -dsu[y] * sz(c[x]) + -dsu[x] * sz(c[y]);

    dsu[x] += dsu[y]; dsu[y] = x;

    A(u, c[y]){
        if(c[x].find(u) != c[x].end()) an += dsu[x];
        else c[x].in(u);
    }

    g[x].erase(y); g[y].erase(x);
    rg[x].erase(x); rg[y].erase(x);

    A(u, g[y]){
        rg[u].erase(y);
        weak(x, u);
    }
    A(u, g[y]){
        g[u].erase(y);
        weak(u, x);
    }
}

int main(){
    int n, m; cin >> n >> m;
    dsu = vi(n, -1);
    c = g = rg = vector<set<int>>(n);
    F(i, n) c[i].in(i);
    while(m--){
        int x, y; cin >> x >> y; x--; y--;
        y = get(y);
        if(get(x) != y && c[y].find(x) == c[y].end()){
            c[y].in(x);
            an -= dsu[y];
            x = get(x);
            weak(x, y);
            while(!todo.empty()){
                auto u = todo.front(); todo.pop();
                merge(u.f, u.s);
            }
        }
        cout << an << endl;
    }
}

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