#include <bits/stdc++.h>
#define PB push_back
using namespace std;
typedef long long ll;
const int N = 100100;
const int M = 200100;
const int oo = 2e9;
vector<int> g[N], gr[N];
int n, m, tin[N], fup[N], tt = 0, U[M], V[M], pr[N], siz[N];
int nw_siz[N];
bool mrk[N], bridge[M];
ll ans = 0, SZ;
void dfs(int v, int p){
mrk[v] = 1;
tin[v] = fup[v] = ++tt;
for (int nm : g[v]){
int u = (U[nm] == v ? V[nm] : U[nm]);
if (u == p) continue;
if (mrk[u])
fup[v] = min(fup[v], tin[u]);
else {
dfs(u, v);
fup[v] = min(fup[v], fup[u]);
if (fup[u] > tin[v])
bridge[nm] = 1;
}
}
}
int get(int x) { return (x == pr[x] ? x : pr[x] = get(pr[x])); }
void dfs1(int v, int p){
nw_siz[v] = siz[v];
mrk[v] = 1;
for (int u : gr[v]){
if (u == p) continue;
dfs1(u, v);
nw_siz[v] += nw_siz[u];
}
}
void dfs2(int v, int p){
ans += ll(siz[v]) * (ll(siz[v]) - 1ll) * (ll(siz[v]) - 2ll) / 2ll; // first
ans += (SZ - ll(siz[v])) * (ll(siz[v]) - 1ll) * (ll(siz[v]) - 1ll);
ll sum = 0ll;
for (int u : gr[v]){
if (u == p) continue;
dfs2(u, v);
ans += sum * ll(siz[v]) * ll(nw_siz[u]);
sum += nw_siz[u];
}
ans += sum * ll(siz[v]) * (SZ - ll(nw_siz[v]));
}
int main(){
ios_base::sync_with_stdio(0); cin.tie(0);
// freopen("in.txt","r",stdin);
cin >> n >> m;
for (int i = 0; i < m; i++){
cin >> U[i] >> V[i];
U[i]--; V[i]--;
g[U[i]].PB(i);
g[V[i]].PB(i);
}
for (int i = 0; i < n; i++) {
if (!mrk[i])
dfs(i, -1);
pr[i] = i;
siz[i] = 1;
}
for (int i = 0; i < m; i++) {
if (bridge[i]) continue;
int x = get(U[i]), y = get(V[i]);
if (x == y) continue;
pr[x] = y;
siz[y] += siz[x];
}
for (int i = 0; i < m; i++)
if (bridge[i]){
int x = get(U[i]), y = get(V[i]);
gr[x].PB(y);
gr[y].PB(x);
}
fill(mrk, mrk + n, 0);
for (int i = 0; i < n; i++){
if (get(i) != i) continue;
if (mrk[i]) continue;
dfs1(i, -1);
SZ = nw_siz[i];
dfs2(i, -1);
}
cout << ans * 2;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
5120 KB |
Output is correct |
2 |
Correct |
7 ms |
5120 KB |
Output is correct |
3 |
Correct |
7 ms |
5120 KB |
Output is correct |
4 |
Correct |
7 ms |
5120 KB |
Output is correct |
5 |
Correct |
9 ms |
5168 KB |
Output is correct |
6 |
Correct |
7 ms |
5120 KB |
Output is correct |
7 |
Incorrect |
7 ms |
5120 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
5120 KB |
Output is correct |
2 |
Correct |
7 ms |
5120 KB |
Output is correct |
3 |
Correct |
7 ms |
5120 KB |
Output is correct |
4 |
Correct |
7 ms |
5120 KB |
Output is correct |
5 |
Correct |
9 ms |
5168 KB |
Output is correct |
6 |
Correct |
7 ms |
5120 KB |
Output is correct |
7 |
Incorrect |
7 ms |
5120 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
90 ms |
18424 KB |
Output is correct |
2 |
Correct |
85 ms |
19772 KB |
Output is correct |
3 |
Correct |
114 ms |
17832 KB |
Output is correct |
4 |
Correct |
96 ms |
19064 KB |
Output is correct |
5 |
Correct |
90 ms |
15992 KB |
Output is correct |
6 |
Correct |
96 ms |
16760 KB |
Output is correct |
7 |
Correct |
101 ms |
15864 KB |
Output is correct |
8 |
Correct |
97 ms |
16504 KB |
Output is correct |
9 |
Correct |
100 ms |
15096 KB |
Output is correct |
10 |
Correct |
106 ms |
15480 KB |
Output is correct |
11 |
Correct |
74 ms |
13688 KB |
Output is correct |
12 |
Correct |
84 ms |
13564 KB |
Output is correct |
13 |
Correct |
65 ms |
13500 KB |
Output is correct |
14 |
Correct |
66 ms |
13264 KB |
Output is correct |
15 |
Correct |
70 ms |
12792 KB |
Output is correct |
16 |
Correct |
53 ms |
12536 KB |
Output is correct |
17 |
Correct |
9 ms |
7168 KB |
Output is correct |
18 |
Correct |
10 ms |
7168 KB |
Output is correct |
19 |
Correct |
10 ms |
7168 KB |
Output is correct |
20 |
Correct |
11 ms |
7168 KB |
Output is correct |
21 |
Correct |
10 ms |
7168 KB |
Output is correct |
22 |
Correct |
10 ms |
7168 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
5248 KB |
Output is correct |
2 |
Correct |
8 ms |
5120 KB |
Output is correct |
3 |
Correct |
8 ms |
5120 KB |
Output is correct |
4 |
Correct |
8 ms |
5248 KB |
Output is correct |
5 |
Correct |
8 ms |
5248 KB |
Output is correct |
6 |
Correct |
8 ms |
5248 KB |
Output is correct |
7 |
Correct |
8 ms |
5248 KB |
Output is correct |
8 |
Correct |
10 ms |
5248 KB |
Output is correct |
9 |
Correct |
7 ms |
5248 KB |
Output is correct |
10 |
Correct |
7 ms |
5120 KB |
Output is correct |
11 |
Correct |
8 ms |
5120 KB |
Output is correct |
12 |
Correct |
7 ms |
5248 KB |
Output is correct |
13 |
Correct |
7 ms |
5120 KB |
Output is correct |
14 |
Correct |
7 ms |
5120 KB |
Output is correct |
15 |
Correct |
7 ms |
5120 KB |
Output is correct |
16 |
Correct |
7 ms |
5120 KB |
Output is correct |
17 |
Correct |
8 ms |
5120 KB |
Output is correct |
18 |
Correct |
7 ms |
5120 KB |
Output is correct |
19 |
Correct |
7 ms |
5120 KB |
Output is correct |
20 |
Correct |
7 ms |
5120 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
96 ms |
14456 KB |
Output is correct |
2 |
Correct |
95 ms |
14456 KB |
Output is correct |
3 |
Correct |
96 ms |
14456 KB |
Output is correct |
4 |
Correct |
118 ms |
14584 KB |
Output is correct |
5 |
Correct |
99 ms |
14456 KB |
Output is correct |
6 |
Correct |
125 ms |
18552 KB |
Output is correct |
7 |
Correct |
115 ms |
17144 KB |
Output is correct |
8 |
Correct |
113 ms |
16376 KB |
Output is correct |
9 |
Correct |
108 ms |
15736 KB |
Output is correct |
10 |
Correct |
105 ms |
14584 KB |
Output is correct |
11 |
Correct |
93 ms |
14456 KB |
Output is correct |
12 |
Correct |
98 ms |
14456 KB |
Output is correct |
13 |
Correct |
94 ms |
14456 KB |
Output is correct |
14 |
Correct |
81 ms |
14200 KB |
Output is correct |
15 |
Correct |
88 ms |
13816 KB |
Output is correct |
16 |
Correct |
51 ms |
12280 KB |
Output is correct |
17 |
Correct |
62 ms |
15088 KB |
Output is correct |
18 |
Correct |
60 ms |
15096 KB |
Output is correct |
19 |
Correct |
62 ms |
15340 KB |
Output is correct |
20 |
Correct |
61 ms |
15096 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
8 ms |
5248 KB |
Output is correct |
2 |
Correct |
7 ms |
5248 KB |
Output is correct |
3 |
Incorrect |
8 ms |
5120 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
96 ms |
14456 KB |
Output is correct |
2 |
Correct |
101 ms |
14456 KB |
Output is correct |
3 |
Incorrect |
97 ms |
13508 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
5120 KB |
Output is correct |
2 |
Correct |
7 ms |
5120 KB |
Output is correct |
3 |
Correct |
7 ms |
5120 KB |
Output is correct |
4 |
Correct |
7 ms |
5120 KB |
Output is correct |
5 |
Correct |
9 ms |
5168 KB |
Output is correct |
6 |
Correct |
7 ms |
5120 KB |
Output is correct |
7 |
Incorrect |
7 ms |
5120 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
7 ms |
5120 KB |
Output is correct |
2 |
Correct |
7 ms |
5120 KB |
Output is correct |
3 |
Correct |
7 ms |
5120 KB |
Output is correct |
4 |
Correct |
7 ms |
5120 KB |
Output is correct |
5 |
Correct |
9 ms |
5168 KB |
Output is correct |
6 |
Correct |
7 ms |
5120 KB |
Output is correct |
7 |
Incorrect |
7 ms |
5120 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |