제출 #829769

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
829769		caganyanmaz	Duathlon (APIO18_duathlon)	C++14	23 / 100	1101 ms	1048576 KiB

count_triplets

#include <bits/stdc++.h>
#define int int64_t
#define pb push_back
using namespace std;

constexpr static int MXN = 1e5;
int n, m;
vector<int> g[MXN];
bitset<MXN> visited;
int subtree_size[MXN];

int res;
void dfs1(int node, int p)
{
	visited[node] = true;
	subtree_size[node] = 1;
	for (int c : g[node])
	{
		if (c == p)
			continue;
		dfs1(c, node);
		subtree_size[node] += subtree_size[c];
	}

}

void dfs2(int node, int p, int sum)
{
	for (int c : g[node])
	{
		if (c == p)
			continue;
		dfs2(c, node, sum);
		res += subtree_size[c] * (sum - subtree_size[c] - 1);
	}
	int rem = sum - subtree_size[node];
	res += (subtree_size[node] - 1) * rem;
}

int32_t main()
{
	cin >> n >> m;
	for (int i = 0; i < m; i++)
	{
		int a, b;
		cin >> a >> b;
		a--,b--;
		g[a].pb(b);
		g[b].pb(a);
	}
	for (int i = 0; i < n; i++)
	{
		if (!visited[i])
		{
			dfs1(i, i);
			dfs2(i, i, subtree_size[i]);
		}
	}
	cout << res << "\n";
}

• 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