#include <bits/stdc++.h>
#define ll long long
using namespace std;
inline bool isin(ll a, unordered_set<ll>& s) {
return s.find(a) != s.end();
}
int main() {
ll n, m, i, a, b, ans = 0;
cin >> n >> m;
vector<vector<ll>> queries(m, vector<ll>(2));
for (i = 0; i < m; i++) cin >> queries[i][0] >> queries[i][1];
vector<unordered_set<ll>> A(n + 1), AB(n + 1), f(n + 1), rf(n + 1);
vector<ll> root(n + 1);
queue<pair<ll, ll>> tomerge;
ll cura, curb;
for (i = 0; i <= n; i++) {
A[i].insert(i);
AB[i].insert(i);
root[i] = i;
}
for (i = 0; i < m; i++) {
a = queries[i][0];
b = queries[i][1];
f[root[a]].insert(root[b]);
rf[root[b]].insert(root[a]);
if (not isin(a, AB[root[b]])) {
AB[root[b]].insert(a);
ans += A[root[b]].size();
}
if (isin(root[a], f[root[b]]) and root[a] != root[b]) tomerge.push(make_pair(root[a], root[b]));
while (not tomerge.empty()) {
cura = tomerge.front().first;
curb = tomerge.front().second;
tomerge.pop();
ans -= A[cura].size() * (AB[cura].size() - 1);
ans -= A[curb].size() * (AB[curb].size() - 1);
if (AB[cura].size() < AB[curb].size()) swap(cura, curb);
for (ll elem : AB[curb]) AB[cura].insert(elem);
for (ll elem : A[curb]) A[cura].insert(elem);
ans += A[cura].size() * (AB[cura].size() - 1);
f[cura].erase(curb);
for (ll elem : f[curb]) {
if (elem == cura) continue;
f[cura].insert(elem);
rf[elem].insert(cura);
rf[elem].erase(curb);
if (isin(cura, f[elem])) tomerge.push(make_pair(elem, cura));
}
for (ll elem : rf[curb]) {
if (elem == cura) continue;
f[elem].insert(cura);
f[elem].erase(curb);
rf[cura].insert(elem);
if (isin(elem, f[cura])) tomerge.push(make_pair(elem, cura));
}
for (ll elem : A[curb]) root[elem] = cura;
}
cout << ans << endl;
}
return 0;
}
/*
6 10
1 2
2 1
3 4
4 3
5 6
6 5
1 3
3 5
5 1
3 1
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Incorrect |
4 ms |
604 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Incorrect |
4 ms |
604 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Incorrect |
4 ms |
604 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |