#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
const int N = 1e5 + 7;
int par[N], sz[N], deg_sz[N], indeg[N];
set <int> comp[N];
set <int> g[N], kek[N];
set <int> gr[N], rg[N];
queue <pair <int, int> > upd;
ll ans = 0;
int get(int v) {
if (v == par[v]) {
return v;
}
return par[v] = get(par[v]);
}
void unite(int a, int b) {
a = get(a), b = get(b);
if (a == b) {
return;
}
if (deg_sz[a] < deg_sz[b]) {
swap(a, b);
}
ans -= sz[a] * (ll) (sz[a] - 1);
ans -= sz[b] * (ll) (sz[b] - 1);
ans -= indeg[a] * (ll) sz[a];
ans -= indeg[b] * (ll) sz[b];
int cur = indeg[a] + indeg[b];
set <int> rem;
for (int v : comp[b]) {
for (int to : gr[v]) {
if (get(to) == a) {
cur--;
rem.insert(v);
break;
}
}
for (int to : rg[v]) {
if (rem.count(to)) {
continue;
}
if (get(to) == a) {
cur--;
rem.insert(to);
} else {
if (kek[to].count(a) && get(to) != b) {
cur--;
rem.insert(to);
}
}
}
}
indeg[a] = cur;
for (int v : comp[b]) {
comp[a].insert(v);
for (int to : gr[v]) {
if (g[get(to)].count(a)) {
upd.push({a, get(to)});
}
}
for (int to : rg[v]) {
g[get(to)].erase(b);
g[get(to)].insert(a);
kek[to].erase(get(b));
kek[to].insert(a);
if (g[a].count(get(to)) && a != get(to)) {
upd.push({a, get(to)});
}
}
}
for (int v : comp[b]) {
comp[a].insert(v);
for (int to : gr[v]) {
if (g[get(to)].count(a)) {
upd.push({a, get(to)});
}
}
for (int to : rg[v]) {
g[get(to)].erase(b);
g[get(to)].insert(a);
kek[to].erase(get(b));
kek[to].insert(a);
if (g[a].count(get(to)) && a != get(to)) {
upd.push({a, get(to)});
}
}
}
sz[a] += sz[b];
deg_sz[a] += deg_sz[b];
par[b] = a;
ans += sz[a] * (ll) (sz[a] - 1);
ans += indeg[a] * (ll) sz[a];
}
int main() {
ios::sync_with_stdio(0);
cin.tie(0);
int n, m;
cin >> n >> m;
for (int i = 1; i <= n; i++) {
sz[i] = 1;
par[i] = i;
deg_sz[i] = 0;
indeg[i] = 0;
comp[i].insert(i);
}
for (int it = 0; it < m; it++) {
int a, b;
cin >> a >> b;
gr[a].insert(b);
rg[b].insert(a);
deg_sz[get(a)]++;
if (get(a) != get(b) && !kek[a].count(get(b))) {
indeg[get(b)]++;
ans += sz[get(b)];
}
kek[a].insert(get(b));
a = get(a);
b = get(b);
g[a].insert(b);
if (g[b].count(a)) {
upd.push({a, b});
}
while (!upd.empty()) {
int a = upd.back().first, b = upd.back().second;
upd.pop();
a = get(a), b = get(b);
if (a == b) {
continue;
}
unite(a, b);
}
cout << ans << '\n';
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
23808 KB |
Output is correct |
| 2 |
Correct |
16 ms |
23808 KB |
Output is correct |
| 3 |
Incorrect |
17 ms |
23936 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
23808 KB |
Output is correct |
| 2 |
Correct |
16 ms |
23808 KB |
Output is correct |
| 3 |
Incorrect |
17 ms |
23936 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
20 ms |
23808 KB |
Output is correct |
| 2 |
Correct |
16 ms |
23808 KB |
Output is correct |
| 3 |
Incorrect |
17 ms |
23936 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
