제출 #700728

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
700728		sunwukong123	조이터에서 친구를 만드는건 재밌어 (JOI20_joitter2)	C++14	100 / 100	1112 ms	94888 KiB

joitter2

#include <bits/stdc++.h>
using namespace std;
#define int long long 
#define FOR(i,s,e) for(int i = s; i <= (int)e; ++i)
#define DEC(i,s,e) for(int i = s; i >= (int)e; --i)
#define IAMSPEED ios_base::sync_with_stdio(false); cin.tie(0);
#ifdef LOCAL
#define db(x) cerr << #x << "=" << x << "\n"
#define db2(x, y) cerr << #x << "=" << x << " , " << #y << "=" << y << "\n"
#define db3(a,b,c) cerr<<#a<<"="<<a<<","<<#b<<"="<<b<<","<<#c<<"="<<c<<"\n"
#define dbv(v) cerr << #v << ":"; for (auto ite : v) cerr << ite << ' '; cerr <<"\n"
#define dbvp(v) cerr << #v << ":"; for (auto ite : v) cerr << "{"  << ite.f << ',' << ite.s << "} "; cerr << "\n"
#define dba(a,ss,ee) cerr << #a << ":"; FOR(ite,ss,ee) cerr << a[ite] << ' '; cerr << "\n"
#define reach cerr << "LINE: " << __LINE__ << "\n";
#else
#define reach 
#define db(x)
#define db2(x,y)
#define db3(a,b,c)
#define dbv(v)
#define dbvp(v)
#define dba(a,ss,ee)
#endif
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define pb push_back
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define f first 
#define s second
#define g0(x) get<0>(x)
#define g1(x) get<1>(x)
#define g2(x) get<2>(x)
#define g3(x) get<3>(x)
typedef pair <int, int> pi;
typedef tuple<int,int,int> ti3;
typedef tuple<int,int,int,int> ti4;
int rand(int a, int b) { return a + rng() % (b-a+1); }
const int MOD = 1e9 + 7;
const int inf = (int)1e9 + 500;
const long long oo = (long long)1e18 + 500;
template <typename T> void chmax(T& a, const T b) { a=max(a,b); }
template <typename T> void chmin(T& a, const T b) { a=min(a,b); }
const int MAXN = 100005;
int n,m;
int ans;
struct ufds_ {
	int p[MAXN], sz[MAXN];
	unordered_set<int> innodes[MAXN];
	unordered_set<int> in[MAXN], out[MAXN];
	ufds_() {
		iota(p,p+MAXN,0);
		fill(sz,sz+MAXN,1);
		FOR(i,0,MAXN-1) {
			innodes[i].insert(i);
		}
	}
	int find(int x) {
		if(x==p[x])return x;
		else return p[x]=find(p[x]);
	}
} ufds;
int pairs(int sz) {
	return sz*(sz-1);
}
int32_t main() 
{
	IAMSPEED
	cin >> n >> m;
	FOR(idx,1,m) {
		int a,b; cin >> a >> b;
		// insert a->b 
		int ga=ufds.find(a);
		int gb=ufds.find(b);
	
		if(ga==gb){
			cout<<ans<<'\n';
			continue;
		}
		
		if(ufds.in[ga].find(gb) != ufds.in[ga].end()) {
			
			queue<pi> q;
			q.push({ga,gb}); // merge ga, gb;
			while(q.size()) {
				pi cur=q.front(); q.pop();
				if(ufds.find(cur.f) == ufds.find(cur.s))continue;
				int x= ufds.find(cur.f), y=ufds.find(cur.s);


				ans-=pairs(ufds.sz[x]);
				ans-=ufds.sz[x] * (ufds.innodes[x].size() - ufds.sz[x]);

				ans-=pairs(ufds.sz[y]);
				ans-=ufds.sz[y] * (ufds.innodes[y].size() - ufds.sz[y]);

				if(ufds.innodes[x].size() < ufds.innodes[y].size())swap(x,y);
				// innodes[x].size() >= innodes[y].size()
				for(auto i:ufds.innodes[y])ufds.innodes[x].insert(i);
				ufds.sz[x]+=ufds.sz[y];
				ufds.p[y] = x;
			
				ans += pairs(ufds.sz[x]);
				
				ans += ufds.sz[x] * (ufds.innodes[x].size() - ufds.sz[x]);
				
				for(auto i:ufds.out[y]) { // these things need to be updated from y to x.
					ufds.in[i].erase(y);
					ufds.in[i].insert(x);
					ufds.out[x].insert(i);
					if(ufds.in[x].find(i) != ufds.in[x].end()) {
						q.push({x,i});
					}

				}
				for(auto i:ufds.in[y]){
					ufds.in[x].insert(i);
					ufds.out[i].erase(y);
					ufds.out[i].insert(x);
					if(ufds.in[i].find(x) != ufds.in[i].end()) {
						q.push({x,i});
					}
				}


			}
			
		} else {
			if(ufds.innodes[gb].find(a) == ufds.innodes[gb].end()) {
				ufds.in[gb].insert(ga);
				ufds.innodes[gb].insert(a);
				ufds.out[ga].insert(gb);

				ans+=ufds.sz[gb];
			}
			
		}
		cout << ans << '\n';
		
	}

	return (0-0) ; 
}

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