#include <bits/stdc++.h>
using namespace std;
const int N = 3e5 + 7;
int n, m;
vector<pair<int, int>> g[N];
vector<int> gr[N];
int dep[N], low[N];
bool vis[N];
int col[N], cnt;
int sz[N];
long long ans;
int S;
void dfs(int v, int p = -1) {
low[v] = dep[v];
vis[v] = true;
for (auto [u, i] : g[v]) {
if (!vis[u]) {
dep[u] = dep[v] + 1;
dfs(u, i);
low[v] = min(low[v], low[u]);
} else {
if (i != p)
low[v] = min(low[v], dep[u]);
}
}
}
void paint(int v, int p = -1) {
vis[v] = true;
for (auto [u, i] : g[v]) {
if (!vis[u]) {
if (dep[v] <= low[u]) {
col[i] = ++cnt;
} else {
col[i] = col[p];
}
paint(u, i);
} else {
if (i != p) {
if (dep[u] < dep[v]) col[i] = col[p];
}
}
}
}
int get_size(int v, int p = -1) {
sz[v] = v <= n;
for (int u : gr[v]) {
if (u != p) {
sz[v] += get_size(u, v);
}
}
return sz[v];
}
void find_ans(int v, int p = -1) {
vis[v] = true;
for (int u : gr[v]) {
if (u != p)
find_ans(u, v);
}
if (v <= n) {
int sum = 0;
for (int u : gr[v]) {
int sz_u = u == p ? S - sz[v] : sz[u];
ans += (long long)sum * sz_u * 2;
sum += sz_u;
}
}
}
int main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
#endif
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n >> m;
for (int i = 1; i <= m; ++i) {
int u, v;
cin >> u >> v;
g[u].push_back({v, i});
g[v].push_back({u, i});
}
for (int i = 1; i <= n; ++i) {
if (!vis[i]) {
dep[i] = 0;
dfs(i);
}
}
for (int i = 1; i <= n; ++i)
vis[i] = false;
cnt = n;
for (int i = 1; i <= n; ++i) {
if (!vis[i]) {
paint(i);
}
}/*
for (int i = 1; i <= m; ++i)
cout << col[i] << " ";
cout << endl;
return 0;*/
for (int i = 1; i <= n; ++i) {
vector<int> v;
for (auto [u, i] : g[i])
v.push_back(col[i]);
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
for (int c : v) {
// cout << min(i, c) << " " << max(i, c) << endl;
gr[i].push_back(c);
gr[c].push_back(i);
}
}
for (int i = 1; i <= cnt; ++i)
vis[i] = false;
ans = 0;
for (int i = 1; i <= cnt; ++i) {
if (!vis[i]) {
S = get_size(i);
find_ans(i);
}
}
cout << ans << endl;
return 0;
}
Compilation message
count_triplets.cpp: In function 'void dfs(int, int)':
count_triplets.cpp:20:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
20 | for (auto [u, i] : g[v]) {
| ^
count_triplets.cpp: In function 'void paint(int, int)':
count_triplets.cpp:34:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
34 | for (auto [u, i] : g[v]) {
| ^
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:109:19: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
109 | for (auto [u, i] : g[i])
| ^
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
10 ms |
14444 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
10 ms |
14444 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
172 ms |
31380 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
14572 KB |
Output is correct |
2 |
Correct |
11 ms |
14592 KB |
Output is correct |
3 |
Correct |
11 ms |
14572 KB |
Output is correct |
4 |
Correct |
11 ms |
14700 KB |
Output is correct |
5 |
Correct |
11 ms |
14724 KB |
Output is correct |
6 |
Correct |
11 ms |
14572 KB |
Output is correct |
7 |
Correct |
11 ms |
14700 KB |
Output is correct |
8 |
Correct |
12 ms |
14572 KB |
Output is correct |
9 |
Correct |
13 ms |
14580 KB |
Output is correct |
10 |
Correct |
11 ms |
14572 KB |
Output is correct |
11 |
Correct |
13 ms |
14572 KB |
Output is correct |
12 |
Correct |
11 ms |
14572 KB |
Output is correct |
13 |
Correct |
11 ms |
14572 KB |
Output is correct |
14 |
Correct |
11 ms |
14572 KB |
Output is correct |
15 |
Correct |
11 ms |
14572 KB |
Output is correct |
16 |
Correct |
12 ms |
14572 KB |
Output is correct |
17 |
Correct |
11 ms |
14572 KB |
Output is correct |
18 |
Correct |
11 ms |
14572 KB |
Output is correct |
19 |
Correct |
12 ms |
14572 KB |
Output is correct |
20 |
Correct |
11 ms |
14572 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
225 ms |
27392 KB |
Output is correct |
2 |
Correct |
225 ms |
27628 KB |
Output is correct |
3 |
Correct |
206 ms |
27500 KB |
Output is correct |
4 |
Correct |
218 ms |
27500 KB |
Output is correct |
5 |
Correct |
189 ms |
27500 KB |
Output is correct |
6 |
Correct |
251 ms |
33644 KB |
Output is correct |
7 |
Correct |
223 ms |
31724 KB |
Output is correct |
8 |
Correct |
228 ms |
30700 KB |
Output is correct |
9 |
Correct |
243 ms |
29420 KB |
Output is correct |
10 |
Correct |
184 ms |
27500 KB |
Output is correct |
11 |
Correct |
195 ms |
27500 KB |
Output is correct |
12 |
Correct |
216 ms |
27500 KB |
Output is correct |
13 |
Correct |
244 ms |
27376 KB |
Output is correct |
14 |
Correct |
193 ms |
26860 KB |
Output is correct |
15 |
Correct |
139 ms |
25964 KB |
Output is correct |
16 |
Correct |
103 ms |
23148 KB |
Output is correct |
17 |
Correct |
141 ms |
28000 KB |
Output is correct |
18 |
Correct |
166 ms |
27996 KB |
Output is correct |
19 |
Correct |
159 ms |
27988 KB |
Output is correct |
20 |
Correct |
149 ms |
27996 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
14572 KB |
Output is correct |
2 |
Correct |
12 ms |
14572 KB |
Output is correct |
3 |
Incorrect |
11 ms |
14700 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
199 ms |
27372 KB |
Output is correct |
2 |
Correct |
222 ms |
27372 KB |
Output is correct |
3 |
Incorrect |
272 ms |
26988 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
10 ms |
14444 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
10 ms |
14444 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |