// Cao Quang Hung
#include <cassert>
#include <cctype>
#include <cerrno>
#include <cfloat>
#include <ciso646>
#include <climits>
#include <clocale>
#include <cmath>
#include <csetjmp>
#include <csignal>
#include <cstdarg>
#include <cstddef>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <ctime>
#include <ccomplex>
#include <cfenv>
#include <cinttypes>
#include <cstdbool>
#include <cstdint>
#include <ctgmath>
#include <cwchar>
#include <cwctype>
#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>
#include <array>
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <forward_list>
#include <future>
#include <initializer_list>
#include <mutex>
#include <random>
#include <ratio>
#include <regex>
#include <scoped_allocator>
#include <system_error>
#include <thread>
#include <tuple>
#include <typeindex>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
using namespace std;
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<long long , long long>
#define vi vector<int>
#define vpii vector<pii>
#define SZ(x) ((int)(x.size()))
#define fi first
#define se second
#define IN(x,y) ((y).find((x))!=(y).end())
#define ALL(t) t.begin(),t.end()
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
#define REPD(i,a,b) for(int (i)=(a); (i)>=(b);--i)
#define FOR(i, n) for (int (i) = 0; (i) < (n); ++(i))
#define dem(x) __builtin_popcount(x)
#define Mask(x) (1LL << (x))
#define BIT(x, i) ((x) >> (i) & 1)
#define ln '\n'
#define io_faster ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
///mt19937 rnd(time(0));
const int INF = 1e9 , mod = 1e9 + 7;
template <class T1, class T2>
inline T1 mul(T1& x, const T2 &k){ return x = (1LL * x * k) % mod; }
template <class T1 , class T2>
inline T1 pw(T1 x, T2 k){T1 res = 1; for (; k ; k >>= 1){ if (k & 1) mul(res, x); mul(x, x); } return res;}
template <class T>
inline bool minimize(T &x, const T &y){ if (x > y){x = y; return 1;} return 0; }
template <class T>
inline bool maximize(T &x, const T &y){ if (x < y){x = y; return 1;} return 0; }
template <class T>
inline void add(T &x , const T &y){ if ((x += y) >= mod) x -= mod; }
template <class T>
inline T product (const T &x , const T &y) { return 1LL * x * y % mod; }
#define PROB "a"
void file(){
if(fopen(PROB".inp", "r")){
freopen(PROB".inp","r",stdin);
freopen(PROB".out","w",stdout);
}
}
void sinh_(){
// srand(time(0));
// freopen(PROB".inp" , "w" , stdout);
// int n;
}
typedef long long ll;
typedef double db;
const int N = 2e5 + 5;
int n, m;
vi adj[N], g[N * 2];
int num[N], low[N], timeDfs(0), numNode;
int f[N*2], sz[N*2], totsize;
stack<int> st;
ll res = 0;
void readip(){
cin >> n >> m;
REP(i, 1, m) {
int u, v; cin >> u >> v;
adj[u].eb(v);
adj[v].eb(u);
}
}
namespace sub3{
bool check() {
REP(i, 1, n) if (adj[i].size() > 2) return false;
return true;
}
vector<bool> vis;
int numNode = 0;
void dfs(int u) {
++numNode;
vis[u] = true;
for (int v : adj[u]) if (!vis[v])
dfs(v);
}
void solve() {
ll res = 0;
vis.assign(n + 2, 0);
REP(i, 1, n) if (!vis[i] && adj[i].size() == 1) {
numNode = 0;
dfs(i);
res += 1LL * numNode * (numNode - 1) * (numNode - 2) / 3;
}
REP(i, 1, n) if (!vis[i] && adj[i].size() == 2) {
numNode = 0;
dfs(i);
res += 1LL * numNode * (numNode - 1) * (numNode - 2);
}
cout << res << ln;
}
};
namespace sub5{
vector<bool> vis;
bool oke = 1;
void dfs(int u, int p) {
if (!oke) return;
vis[u] = 1;
for (int v : adj[u]) if (v != p) {
if (vis[v]) {
oke = 0;
return;
}
dfs(v, u);
}
}
bool check() {
vis.assign(n + 2, 0);
REP(i, 1, n) if (!vis[i]) dfs(i, -1);
return oke;
}
ll res = 0;
int cnt = 0;
vector<int> sz, mark, Size;
void dfs_tree(int u, int p) {
mark[u] = cnt;
sz[u] = 0;
for (int v : adj[u]) if (v != p) {
dfs_tree(v, u);
res += 2LL * sz[u] * sz[v];
sz[u] += sz[v];
}
++sz[u];
}
void solve() {
sz.assign(n + 2, 0);
mark.assign(n + 2, -1);
REP(i, 1, n) if (mark[i] == -1) {
dfs_tree(i, -1);
Size.eb(sz[i]);
++cnt;
}
REP(i, 1, n) {
res += 2LL * (sz[i] - 1) * (Size[mark[i]] - sz[i]);
}
cout << res << ln;
}
};
namespace subfull {
struct DSU{
int par[N], sz[N];
int root(int x) {
if (x == par[x]) return x;
return par[x] = root(par[x]);
}
void unite(int u, int v) {
u = root(u) , v = root(v);
if (u == v) return;
if (sz[u] < sz[v]) swap(u, v);
sz[u] += sz[v];
par[v] = u;
}
void process() {
REP(i, 1, n) par[i] = i, sz[i] = 1;
REP(u, 1, n) for (int v : adj[u])
unite(u, v);
}
} dsu;
void add_edge(int u, int v) {
g[u].eb(v);
g[v].eb(u);
// cout << u << ' ' << v << ln;
}
void dfs(int u) {
num[u] = low[u] = ++timeDfs;
st.push(u);
for (int v : adj[u]) {
if (num[v]) minimize(low[u], num[v]);
else {
dfs(v);
minimize(low[u], low[v]);
if (num[u] == low[v]) {
++numNode;
add_edge(u, numNode);
int x = -1, cnt(0);
do {
x = st.top();
st.pop();
add_edge(x, numNode);
++cnt;
} while(x != v) ;
f[numNode] = cnt;
/// case 1: s, c, f in one biconnected component
res += 1LL * (cnt + 1) * (cnt) * (cnt - 1);
/// case 2: 2 vertices in one biconnected component, and the remain vertex in another one.
res += 2LL * cnt * (cnt - 1) * (dsu.sz[dsu.root(u)] - cnt - 1);
}
}
}
}
void dfs_tree(int u, int p) {
sz[u] = 0;
for (int v : g[u]) if (v != p) {
dfs_tree(v, u);
if (u <= n) {
res += 2LL * sz[u] * sz[v];
sz[u] += sz[v];
}
else {
// res += 2LL * f[u] * sz[u] * (sz[v] - 1);
sz[u] += sz[v] - 1;
}
}
if (u <= n) ++sz[u];
else sz[u] += f[u];
// if (u <= n) {
// res += 2LL * (totsize - sz[u]) * (sz[u] - 1);
// cout << u << ' ' << 2LL * (totsize - sz[u]) * (sz[u] - 1) << ln;
// }
// else {}
if (u > n) {
res += 2LL * (totsize - sz[u]) * f[u] * (sz[u] - f[u]);
cout << u << ' ' << f[u] << ' ' << (totsize - sz[u]) << ' ' << sz[u] - f[u] << ln;
// 2LL * (totsize - sz[u]) * f[u] * (sz[u] - f[u]) << ln;
}
}
void solve() {
numNode = n;
dsu.process();
REP(i, 1, n) if (dsu.root(i) == i) {
totsize = dsu.sz[i];
dfs(i);
dfs_tree(i, -1);
}
cout << res << ln;
}
};
void solve(){
// if (sub3::check()) {
// sub3::solve();
// return;
// }
// if (sub5::check()) {
// sub5::solve();
// return;
// }
subfull::solve();
}
int main(){
sinh_();
io_faster
file();
int t = 1;
// cin >> t;
while (t--){
readip();
solve();
}
}
Compilation message
count_triplets.cpp: In function 'void readip()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:148:5: note: in expansion of macro 'REP'
148 | REP(i, 1, m) {
| ^~~
count_triplets.cpp: In function 'bool sub3::check()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:157:9: note: in expansion of macro 'REP'
157 | REP(i, 1, n) if (adj[i].size() > 2) return false;
| ^~~
count_triplets.cpp: In function 'void sub3::solve()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:174:9: note: in expansion of macro 'REP'
174 | REP(i, 1, n) if (!vis[i] && adj[i].size() == 1) {
| ^~~
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:179:9: note: in expansion of macro 'REP'
179 | REP(i, 1, n) if (!vis[i] && adj[i].size() == 2) {
| ^~~
count_triplets.cpp: In function 'bool sub5::check()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:205:9: note: in expansion of macro 'REP'
205 | REP(i, 1, n) if (!vis[i]) dfs(i, -1);
| ^~~
count_triplets.cpp: In function 'void sub5::solve()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:226:9: note: in expansion of macro 'REP'
226 | REP(i, 1, n) if (mark[i] == -1) {
| ^~~
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:231:9: note: in expansion of macro 'REP'
231 | REP(i, 1, n) {
| ^~~
count_triplets.cpp: In member function 'void subfull::DSU::process()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:255:13: note: in expansion of macro 'REP'
255 | REP(i, 1, n) par[i] = i, sz[i] = 1;
| ^~~
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'u' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:256:13: note: in expansion of macro 'REP'
256 | REP(u, 1, n) for (int v : adj[u])
| ^~~
count_triplets.cpp: In function 'void subfull::solve()':
count_triplets.cpp:92:28: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
92 | #define REP(i,a,b) for(int (i)=(a);(i)<=(b);++i)
| ^
count_triplets.cpp:329:9: note: in expansion of macro 'REP'
329 | REP(i, 1, n) if (dsu.root(i) == i) {
| ^~~
count_triplets.cpp: In function 'void file()':
count_triplets.cpp:125:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
125 | freopen(PROB".inp","r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
count_triplets.cpp:126:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
126 | freopen(PROB".out","w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
20572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
20572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
52 ms |
41568 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
13 ms |
20572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
93 ms |
31884 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
20568 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
107 ms |
32340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
20572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
5 ms |
20572 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
