제출 #405482

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
405482		saleh	철인 이종 경기 (APIO18_duathlon)	C++17	8 / 100	89 ms	13300 KiB

count_triplets

#include <bits/stdc++.h>

#define int long long

using namespace std;


const int MAXN = 100 * 1000 + 23;















int n, m, ans;
vector<int> g[MAXN];
bitset<MAXN> mark, mirk;

//int ent(int x) { return x * (x - 1); }
int gs(int v, int p) {
	int res = 1;
	mark[v] = true;
	for (auto i : g[v]) if (!mark[i]) res += gs(i, v);
	return res;
}
int ds(int v, int p) {
	int res = g[v].size();
	mirk[v] = true;
	for (auto i : g[v]) if (i != p && !mirk[i]) res += ds(i, v);
	return res;
}


int32_t main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr), cout.tie(nullptr);
	cin >> n >> m;
	for (int i = 0; i < m; i++) {
		int u, v;
		cin >> u >> v;
		g[--u].push_back(--v), g[v].push_back(u);
	}
	for (int i = 0; i < n; i++) if (!mark[i]) {
		int x = gs(i, -1);
		int y = ds(i, -1);
		if (x * 2 == y) ans += x * (x - 1) * (x - 2);
		else for (int i = 0; i < x; i++) ans += i * (x - i - 1) * 2;
	}
	cout << ans;
	return 0;
}

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