Submission #92515

#	Time	Username	Problem	Language	Result	Execution time	Memory
92515		antimirage	철인 이종 경기 (APIO18_duathlon)	C++14	23 / 100	1102 ms	1049600 KiB

count_triplets

#include <bits/stdc++.h>
 
#define fr first
#define sc second
#define mk make_pair
#define pb emplace_back
#define all(s) s.begin(), s.end()
 
using namespace std;

const int N = 1e5 + 5;

int n, m, x, y, cn;

vector < vector <int> > g;

long long ans, u[N];

void dfs (int v)
{
	u[v] = 1;
	for (auto to : g[v])
	{
		if (u[to]) continue;
		dfs(to);
		u[v] += u[to];
	}
}
void dfs2 (int v, int root, int p = 0)
{
	ans +=( u[root] - u[v]) * (u[v] - 1) * 2;
	
	for (auto to : g[v])
	{
		if (to == p) continue;
		dfs2(to, root, v);
		
		ans += (u[v] - u[to] - 1) * u[to];
	}
}
main() 
{
	cin >> n >> m;
	g.resize(n + 1);
	
	for (int i = 1; i <= m; i++)
	{
		scanf("%d%d", &x, &y);
		g[x].pb(y);
		g[y].pb(x);
	}
	for (int i = 1; i <= n; i++)
	{
		if (u[i]) continue;
		
		dfs(i);		
		dfs2(i, i);
	}
	cout << ans << endl;
}

Compilation message (stderr)

count_triplets.cpp:41:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() 
      ^
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:48:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", &x, &y);
   ~~~~~^~~~~~~~~~~~~~~~

• 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