#include <bits/stdc++.h>
// #pragma GCC optimize("O3", "unroll-loops")
#define ll long long
#define int long long
#define pb push_back
#define fi first
#define se second
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<pii, int> ipii;
const int MAXN = 1e5+10;
const int MAXA = 9e3+20;
const ll INF = 1e18+10;
const int LOG = 20;
const int SQRT = 450;
int done[MAXN], DONE;
int n, m;
int u[MAXN], v[MAXN];
vector <int> adj[MAXN];
int disc[MAXN], low[MAXN], tim, chi[MAXN];
int ap[MAXN], color, col[MAXN];
int sub[MAXN], val[MAXN];
int cnt[MAXN];
void dfs(int nw, int par){
done[nw] = DONE;
disc[nw] = low[nw] = ++tim;
for(auto nx : adj[nw]){
if(nx==par) continue;
if(disc[nx]!=0) low[nw] = min(low[nw], disc[nx]);
else {
chi[nw]++;
dfs(nx, nw);
if(nw!=1 && low[nx] >= disc[nw]) ap[nw] = 1;
low[nw] = min(low[nw], low[nx]);
}
}
if(chi[nw]>=2 && nw==1) ap[nw] = 1;
if(ap[nw]){
col[nw] = ++color; val[col[nw]] = 1;
}
}
void COL(int nw, int ty){
done[nw] = DONE;
col[nw] = ty; val[ty]++;
for(auto nx : adj[nw]){
if(ap[nx]==1 || col[nx]!=0) continue;
COL(nx, ty);
}
}
vector <int> edge[MAXN];
int ANS, root[MAXN];
void trav(int nw, int par, int roo){
cnt[nw]++;
if(cnt[nw]>1) assert(false);
//S - C - F
done[nw] = DONE;
int te = 0, bef = 0; root[nw] = roo;
sub[nw] = val[nw];
for(auto nx : edge[nw]){
if(done[nx]==DONE) continue;
trav(nx, nw, roo);
sub[nw] += sub[nx];
te += bef*sub[nx]*2;
bef += sub[nx];
}
ANS += te*val[nw];
}
void bd(int nw, int par){
cnt[nw]++;
if(cnt[nw]>2) assert(false);
for(auto nx : edge[nw]){
if(done[nx]==DONE) continue;
bd(nx, nw);
}
int up = sub[root[nw]]-sub[nw], dw = sub[nw]-val[nw];
int te = up*dw*2;
// cout << nw << ' ' << te << " te\n";
ANS += te*val[nw];
}
signed main(){
// ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
cin >> n >> m;
for(int i=1; i<=m; i++){
cin >> u[i] >> v[i];
adj[u[i]].pb(v[i]); adj[v[i]].pb(u[i]);
}
DONE++;
for(int i=1; i<=n; i++){
if(done[i]!=DONE) dfs(i, 0);
}
DONE++;
for(int i=1; i<=n; i++){
if(col[i]==0) COL(i, ++color);
}
for(int i=1; i<=m; i++){
int x = col[u[i]], y = col[v[i]];
if(x==y) continue;
edge[x].pb(y); edge[y].pb(x);
}
for(int i=1; i<=color; i++){
sort(edge[i].begin(), edge[i].end());
edge[i].resize(unique(edge[i].begin(), edge[i].end())-edge[i].begin());
}
// for(int i=1; i<=color; i++){
// cout << i << ' ' << val[i] << " val\n";
// }
// for(int i=1; i<=n; i++){
// cout << i << ' ' << disc[i] << ' ' << low[i] << ' ' << chi[i] << ' '<<col[i] << " col\n";
// }
DONE++;
for(int i=1; i<=color; i++){
if(done[i]!=DONE){ trav(i, -1, i); bd(i, -1); }
}
// cout << ANS << " ans1\n";
// SCF
for(int i=1; i<=color; i++){
if(val[i]>=3) ANS += val[i]*(val[i]-1)*(val[i]-2);
}
// cout << ANS << " ans2\n";
// SC-F atau S-CF
for(int i=1; i<=color; i++){
if(val[i]>=2){
int siz = sub[root[i]];
ANS += val[i]*(val[i]-1)*(siz-val[i])*2;
int tot = 0;
for(auto nx : edge[i]) tot += val[nx];
ANS += val[i]*(val[i]-1)*tot;
}
}
cout << ANS << '\n';
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
5980 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Correct |
2 ms |
6748 KB |
Output is correct |
4 |
Correct |
2 ms |
5980 KB |
Output is correct |
5 |
Correct |
2 ms |
6748 KB |
Output is correct |
6 |
Correct |
2 ms |
5980 KB |
Output is correct |
7 |
Incorrect |
2 ms |
6748 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
5980 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Correct |
2 ms |
6748 KB |
Output is correct |
4 |
Correct |
2 ms |
5980 KB |
Output is correct |
5 |
Correct |
2 ms |
6748 KB |
Output is correct |
6 |
Correct |
2 ms |
5980 KB |
Output is correct |
7 |
Incorrect |
2 ms |
6748 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
64 ms |
19792 KB |
Output is correct |
2 |
Correct |
59 ms |
19876 KB |
Output is correct |
3 |
Incorrect |
65 ms |
21448 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
2 ms |
7000 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
70 ms |
21928 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
2 ms |
7004 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
74 ms |
21840 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
5980 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Correct |
2 ms |
6748 KB |
Output is correct |
4 |
Correct |
2 ms |
5980 KB |
Output is correct |
5 |
Correct |
2 ms |
6748 KB |
Output is correct |
6 |
Correct |
2 ms |
5980 KB |
Output is correct |
7 |
Incorrect |
2 ms |
6748 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
5980 KB |
Output is correct |
2 |
Correct |
2 ms |
6748 KB |
Output is correct |
3 |
Correct |
2 ms |
6748 KB |
Output is correct |
4 |
Correct |
2 ms |
5980 KB |
Output is correct |
5 |
Correct |
2 ms |
6748 KB |
Output is correct |
6 |
Correct |
2 ms |
5980 KB |
Output is correct |
7 |
Incorrect |
2 ms |
6748 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |