#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include "temp.cpp"
#include <cstdio>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
#define sz(x) (int)x.size()
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt __builtin_popcount
#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
// template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(Tree <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
// for random generations
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
// mt19937 myrand(131);
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
fastIO();
if(str == "input") {
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
} else if(str != "") {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
}
const int N = 2e5 + 10;
vector<int> adj[N];
bool vis[N], vis2[N];
int dp[51][51][51];
long long n, m, ans;
int st;
void dfs_slow(int node, vector<int> &cur, int d = 0) {
vis[node] = true;
if(d >= 2) {
for(int i = 1; i < sz(cur) - 1; i++) {
dp[st][cur[i]][node] = 1;
}
}
for(auto i: adj[node]) {
if(vis[i]) continue;
cur.push_back(i);
dfs_slow(i, cur, d + 1);
cur.pop_back();
}
vis[node] = false;
}
long long sub[N];
void dfs(int node, int parent) {
sub[node] = 1;
for(auto i: adj[node]) {
if(i == parent) continue;
dfs(i, node);
sub[node] += sub[i];
}
}
bool visss[N];
int c = 0;
void con(int node) {
visss[node] = true;
c++;
for(auto i: adj[node]) {
if(visss[i]) continue;
con(i);
}
}
void solve_() {
cin >> n >> m;
for(int i = 1; i <= m; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
if(n <= 10) {
// for(int i = 1; i<= n;i++) {
con(1);
assert(c == n);
// }
for(int i = 1; i <= n; i++) {
st = i;
vector<int> vec{i};
dfs_slow(i, vec);
}
for(int i = 1; i <= n; i++) {
for(int j = 1; j <= n; j++) {
for(int k = 1; k <= n; k++) {
ans += dp[i][j][k];
}
}
}
cout << ans << '\n';
} else {
ans = 0;
assert(m == n - 1);
ans = 0;
for(int i = 1; i <= n; i++) {
dfs(i, 0);
assert(sub[i] == n);
long long al = sub[i] - 1;
for(auto j: adj[i]) {
ans += (al - sub[j]) * sub[j];
al -= sub[j];
}
}
cout << 2 * ans << '\n';
}
}
int main() {
setIO();
auto solve = [&](int test_case)-> void {
for(int i = 1; i <= test_case; i++) {
solve_();
}
};
int test_cases = 1;
// cin >> test_cases;
solve(test_cases);
return 0;
}
Compilation message
count_triplets.cpp: In function 'void setIO(std::string)':
count_triplets.cpp:76:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
76 | freopen("input.txt", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
count_triplets.cpp:77:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
77 | freopen("output.txt", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
count_triplets.cpp:79:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
79 | freopen((str + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
count_triplets.cpp:80:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
80 | freopen((str + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
9940 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
9940 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
30 ms |
16324 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
9 ms |
5076 KB |
Output is correct |
| 2 |
Correct |
9 ms |
5076 KB |
Output is correct |
| 3 |
Correct |
9 ms |
5076 KB |
Output is correct |
| 4 |
Correct |
15 ms |
5076 KB |
Output is correct |
| 5 |
Correct |
12 ms |
5076 KB |
Output is correct |
| 6 |
Correct |
11 ms |
5076 KB |
Output is correct |
| 7 |
Correct |
14 ms |
5076 KB |
Output is correct |
| 8 |
Correct |
14 ms |
5204 KB |
Output is correct |
| 9 |
Correct |
11 ms |
5112 KB |
Output is correct |
| 10 |
Runtime error |
6 ms |
10068 KB |
Execution killed with signal 6 |
| 11 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1086 ms |
8996 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
9 ms |
5076 KB |
Output is correct |
| 2 |
Correct |
9 ms |
5076 KB |
Output is correct |
| 3 |
Runtime error |
7 ms |
10108 KB |
Execution killed with signal 6 |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1063 ms |
9008 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
9940 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
9940 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
