Submission #213403

#	Time	Username	Problem	Language	Result	Execution time	Memory
213403		_7_7_	Making Friends on Joitter is Fun (JOI20_joitter2)	C++14	100 / 100	1592 ms	119620 KiB

joitter2

#include <bits/stdc++.h>                                           
 
#define int long long
//#pragma GCC optimize("Ofast")
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4")
 
 
#define file(s) freopen(s".in","r",stdin); freopen(s".out","w",stdout);
#define all(x) x.begin(), x.end()
#define sz(s) (int)s.size()
#define pb push_back
#define ppb pop_back
#define mp make_pair
#define s second
#define f first
 
 
using namespace std;
 
 
typedef pair < long long, long long > pll;    
typedef pair < int, int > pii;
typedef unsigned long long ull;         
typedef vector < pii > vpii;
typedef vector < int > vi;
typedef long double ldb;  
typedef long long ll;  
typedef double db;                             
 
 
const int inf = 1e9, maxn = 4e5 + 148, mod = 1e9 + 7, N = 1e5 + 11;
const int dx[] = {1, -1, 0, 0}, dy[] = {0, 0, 1, -1}, block = 333;
const pii base = mp(1171, 3307), Mod = mp(1e9 + 7, 1e9 + 9);
const db eps = 1e-12, pi = 3.14159265359;
const ll INF = 1e18;



unordered_set < int > in[N], out[N], gc[N], g[N], gr[N];
unordered_map < int, int > cnt1[N];
int p[N], ans, n, m, v, u, cnt[N];
queue < pii > q;
vi comp[N];

int get (int v) {
	return p[v] == v ? v : p[v] = get(p[v]);
}

void merge (int v, int u) {
	v = get(v), u = get(u);

	if (v == u)
		return;

	ans -= cnt1[v][u] * cnt[v];
	ans -= cnt1[u][v] * cnt[u];
	ans += 2 * cnt[v] * cnt[u];

	if (cnt[v] + sz(g[v]) < cnt[u] + sz(g[u]))
		swap(v, u);

	for (auto x : comp[u])
		if (g[v].count(x)) {
			g[v].erase(x);
			gr[x].erase(v);
		}

	ans += sz(g[v]) * cnt[u];

	for (auto x : g[u]) {
		if (get(x) == v)
			continue;

		if (g[v].count(x))
			ans -= cnt[u];//common vertex 
		else {
			g[v].insert(x);	
			gr[x].insert(v);
			gr[x].erase(u);
			++cnt1[v][get(x)];
			ans += cnt[v];
		}

		x = get(x);
		gc[v].insert(x);
		if (gc[x].count(v))
			q.push({v, x});
	}

	for (auto x : comp[u])
		for (auto y : gr[x]) {
			if (y == v)
				continue;
			++cnt1[y][v];
			gc[y].insert(v);
			if (gc[v].count(y))
				q.push({v, y});
		}

	p[u] = v;
	cnt[v] += cnt[u];

	for (auto x : comp[u])
		comp[v].pb(x);		
}                       




main () {
	scanf("%lld%lld", &n, &m);
	for (int i = 1; i <= n; ++i) {
		p[i] = i;
		cnt[i] = 1;
		comp[i].pb(i);
	}

	while (m--) {
		scanf("%lld%lld", &u, &v);
		int V = get(v), U = get(u);
		if (V != U) {
			if (gc[U].count(V)) 
				q.push({V, U});
			else {
				gc[V].insert(U);
				if (!g[V].count(u)) {
					++cnt1[V][U];
					ans += cnt[V];
					g[V].insert(u);
					gr[u].insert(V);
				}
			}
			
			while (sz(q)) {
				merge(q.front().f, q.front().s);
				q.pop();
			}
		}
		printf("%lld\n", ans);
	}
}

Compilation message (stderr)

joitter2.cpp:111:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main () {
       ^
joitter2.cpp: In function 'int main()':
joitter2.cpp:112:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~~~~~
joitter2.cpp:120:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld", &u, &v);
   ~~~~~^~~~~~~~~~~~~~~~~~~~

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