#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T, typename U> using ordered_map = tree<T, U, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef string str;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef vector<str> vstr;
#define FOR(i,j,k,in) for(int i=(j); i < (k);i+=in)
#define FORD(i,j,k,in) for(int i=(j); i >=(k);i-=in)
#define REP(i,b) FOR(i,0,b,1)
#define REPD(i,b) FORD(i,b,0,1)
#define pb push_back
#define mp make_pair
#define ff first
#define ss second
#define all(x) begin(x), end(x)
#define rsz resize
const double EPS = 1e-9;
const int MOD = 1e9+7; // 998244353;
const ll INFF = 1e18;
const int INF = 1e9;
const ld PI = acos((ld)-1);
const vi dy = {1, 0, -1, 0, -1, 1, 1, -1};
const vi dx = {0, 1, 0, -1, -1, 1, -1, 1};
#ifdef DEBUG
#define DBG if(1)
#else
#define DBG if(0)
#endif
#define dbg(x) cout << "(" << #x << " : " << x << ")" << endl;
// ostreams
template <class T, class U>
ostream& operator<<(ostream& out, const pair<T, U> &par) {out << "[" << par.first << ";" << par.second << "]"; return out;}
template <class T>
ostream& operator<<(ostream& out, const set<T> &cont) { out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template <class T, class U>
ostream& operator<<(ostream& out, const map<T, U> &cont) {out << "{"; for( const auto &x:cont) out << x << ", "; out << "}"; return out; }
template<class T>
ostream& operator<<(ostream& out, const vector<T> &v){ out << "["; REP(i, v.size()) out << v[i] << ", "; out << "]"; return out;}
// istreams
template<class T>
istream& operator>>(istream& in, vector<T> &v){ for(auto &x : v) in >> x; return in; }
template<class T, class U>
istream& operator>>(istream& in, pair<T, U> &p){ in >> p.ff >> p.ss; return in; }
//searches
template<typename T, typename U>
T bsl(T lo, T hi, U f){ hi++; T mid; while(lo < hi){ mid = (lo + hi)/2; f(mid) ? hi = mid : lo = mid+1; } return lo; }
template<typename U>
double bsld(double lo, double hi, U f, double p = 1e-9){ int r = 3 + (int)log2((hi - lo)/p); double mid; while(r--){ mid = (lo + hi)/2; f(mid) ? hi = mid : lo = mid; } return (lo + hi)/2; }
template<typename T, typename U>
T bsh(T lo, T hi, U f){ lo--; T mid; while(lo < hi){ mid = (lo + hi + 1)/2; f(mid) ? lo = mid : hi = mid-1; } return lo; }
template<typename U>
double bshd(double lo, double hi, U f, double p = 1e-9){ int r = 3+(int)log2((hi - lo)/p); double mid; while(r--){ mid = (lo + hi)/2; f(mid) ? lo = mid : hi = mid; } return (lo + hi)/2; }
// some more utility functions
template<typename T>
pair<T, int> get_min(vector<T> &v){ typename vector<T> :: iterator it = min_element(v.begin(), v.end()); return mp(*it, it - v.begin());}
template<typename T>
pair<T, int> get_max(vector<T> &v){ typename vector<T> :: iterator it = max_element(v.begin(), v.end()); return mp(*it, it - v.begin());}
template<typename T> bool ckmin(T& a, const T& b){return b < a ? a = b , true : false;}
template<typename T> bool ckmax(T& a, const T& b){return b > a ? a = b, true : false;}
// centroid decomposition of a biconnected component tree dafuq
// first only centoid decomp to pass those subtasks
template<typename T>
struct edge{
int src;
int dest;
T cost;
};
template<typename T>
class graph{
public:
vector<edge<T>> edges;
vector<vector<int>> adj;
int n;
graph(){};
graph(int _n){
n = _n;
adj.resize(n);
}
};
template<typename T>
class undigraph : public graph<T>{
public:
using graph<T>::edges;
using graph<T>::adj;
using graph<T>::n;
undigraph() : graph<T>(){};
undigraph(int _n) : graph<T>(_n){};
int add_edge(int src, int dest, T cost = 1){
int id = edges.size();
edges.push_back({src, dest, cost});
adj[src].push_back(id);
adj[dest].push_back(id);
return id;
}
};
int OneCentroid(int root, graph<int> &g, vector<bool> &dead){
vi sz(g.n);
function<void (int, int)> get_sz = [&](int v, int p){
sz[v] = 1;
for(int id : g.adj[v]){
edge<int> e = g.edges[id];
int other = e.src ^ e.dest ^ v;
if(other != p && !dead[other]){
get_sz(other, v);
sz[v] += sz[other];
}
}
};
get_sz(root, -1);
int n = sz[root];
function<int (int, int)> dfs = [&](int v, int p){
for(int id : g.adj[v]){
edge<int> e = g.edges[id];
int other = e.src ^ e.dest ^ v;
if(other != p && !dead[other] && sz[other] > n / 2) return dfs(other, v);
}
return v;
};
return dfs(root, -1);
}
ll CentroidDecomposition(graph<int> &g){
ll ans = 0;
vector<bool> dead(g.n, false);
vector<bool> visited(g.n, false);
function<void (int)> rec = [&](int start){
int c = OneCentroid(start, g, dead);
dead[c] = true;
visited[c] = true;
for(int id : g.adj[c]){
edge<int> e = g.edges[id];
int other = e.src ^ e.dest ^ c;
if(!dead[other]) rec(other);
};
// process centroid;
vi sz(g.n);
function<void (int, int)> get_sz = [&](int v, int p){
sz[v] = 1;
for(int id : g.adj[v]){
edge<int> e = g.edges[id];
int other = e.src ^ e.dest ^ v;
if(other != p && !dead[other]) {
get_sz(other, v);
sz[v] += sz[other];
}
}
};
get_sz(c, -1);
vi children;
for(int id : g.adj[c]){
edge<int> e = g.edges[id];
int other = e.src ^ e.dest ^ c;
if(!dead[other]) children.pb(sz[other]);
}
ll sum = 0;
for(auto x : children) sum += x;
for(auto x : children){
ans += (ll)x * (sum - (ll)x);
}
// end process centoid
dead[c] = false;
};
REP(i, g.n){
if(!visited[i]) rec(i);
}
return 2*ans;
}
struct AcAutomaton{
int n, m;
undigraph<int> g;
void read_in(){
cin >> n >> m;
g = undigraph<int>(n);
REP(i, m){
pii e; cin >> e;
e.ff--; e.ss--;
g.add_edge(e.ff, e.ss);
}
}
void solve(){
ll ans = CentroidDecomposition(g);
cout << ans << endl;
}
};
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
int tcase = 1;
while(tcase--){
AcAutomaton solver;
solver.read_in();
solver.solve();
}
return 0;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
858 ms |
1048580 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
858 ms |
1048580 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1101 ms |
307032 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1095 ms |
7468 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
384 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
1076 ms |
7604 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
858 ms |
1048580 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
858 ms |
1048580 KB |
Execution killed with signal 9 |
| 2 |
Halted |
0 ms |
0 KB |
- |
