Submission #414525

#	Time	Username	Problem	Language	Result	Execution time	Memory
414525		hhhhaura	Duathlon (APIO18_duathlon)	C++14	23 / 100	1091 ms	30164 KiB

count_triplets

#define wiwihorz
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma loop-opt(on)

#define rep(i, a, b) for(int i = a; i <= b; i++)
#define rrep(i, a, b) for(int i = b; i >= a; i--)
#define ceil(a, b) ((a + b - 1) / (b))
#define all(x) x.begin(), x.end()

#define INF 1000000000000000000
#define MOD 1000000007
#define eps (1e-9)

using namespace std;

#define int long long int
#define lld long double
#define pii pair<int, int>
#define random mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count())

#ifdef wiwihorz
#define print(a...) kout("[" + string(#a) + "] = ", a)
void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
void kout() { cerr << endl; }
template<class T1, class ... T2> void kout(T1 a, T2 ... e) { cerr << a << " ", kout(e...);}
#else
#define print(...) 0
#define vprint(...) 0
#endif
namespace solver {
	int n, timestamp, ii, bccid, ans, cnt;
	vector<int> L, D, pre, es, sz;
	vector<vector<int>> mp1, mp2;
	void init_(int _n) {
		n = _n, timestamp = 0;
		ii = 0, bccid = 0, ans = 0;
		L.assign(n + 1, 0);
		D.assign(n + 1, 0);
		pre.assign(n + 1, 0);
		mp1.assign(n + 1, vector<int>());
		mp2.assign(2 * n + 1, vector<int>());
		sz.assign(2 * n + 1, 0);
	}
	void add_edge(int a, int b) {
		mp1[a].push_back(es.size());
		mp1[b].push_back(es.size());
		es.push_back(a ^ b);
	}
	void dfs1(int x, int par) {
		cnt ++, pre[ii++] = x;
		L[x] = D[x] = ++timestamp;
		for(auto i : mp1[x]) if(i != par) {
			int to = es[i] ^ x;
			if(D[to]) L[x] = min(D[to], L[x]);
			else {
				dfs1(to, i);
				L[x] = min(L[x], L[to]);
				if(L[to] >= D[x]) {
					bccid ++;
					mp2[n + bccid].push_back(x);
					mp2[x].push_back(n + bccid);
					while(pre[ii] != to) {
						ii --;
						mp2[n + bccid].push_back(to);
						mp2[to].push_back(n + bccid);
					}
				}
			}
		}
		return;
	}
	void dfs2(int x, int par) {
		if(x <= n) sz[x] = 1;
		for(auto i : mp2[x]) if(i != par) {
			dfs2(i, x), sz[x] += sz[i];
			if(x > n) ans -= (mp2[x].size() - 1) * sz[i] * (sz[i] - 1);  
		} 
		if(x > n) ans -= (mp2[x].size() - 1) * (cnt - sz[x]) * (cnt - sz[x] - 1);
	}
	int solve() {
		rep(i, 1, n) if(!D[i]) {
			cnt = 0, dfs1(i, -1); 
			ans += cnt * (cnt - 1) * (cnt - 2);
			dfs2(i, i);
		}
		return ans;
	}
};
using namespace solver;
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	int n, m; cin >> n >> m;
	init_(n);
	rep(i, 1, m) {
		int a, b; cin >> a >> b;
		add_edge(a, b);
	}
	cout << solve() << "\n";
	return 0;

}

Compilation message (stderr)

count_triplets.cpp:4: warning: ignoring '#pragma loop ' [-Wunknown-pragmas]
    4 | #pragma loop-opt(on)
      | 
count_triplets.cpp:24:13: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   24 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
      |             ^~~~
count_triplets.cpp:24:21: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   24 | void vprint(auto L, auto R) { while(L < R) cerr << *L << " \n"[next(L) == R], ++L;}
      |                     ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 8
• Subtask 4: 10 / 10
• Subtask 5: 13 / 13
• Subtask 6: 0 / 15
• Subtask 7: 0 / 20
• Subtask 8: 0 / 8
• Subtask 9: 0 / 10