Submission #497198

#	Time	Username	Problem	Language	Result	Execution time	Memory
497198		CyberCow	Shymbulak (IZhO14_shymbulak)	C++17	0 / 100	1561 ms	8756 KiB

shymbulak

#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <string>
#include <cmath>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <fstream>
#include <iomanip>
#include <iterator>
#include <stack>
#include <deque>
using namespace std;
using ll = long long;
vector<int> v[200004];
queue<int> q;
int color[200004], ans = 0, n, ma, c[200004];

void solve()
{
	int i, j, x, y, oo = 1000000000;
	cin >> n;
	for ( i = 0; i < n; i++)
	{
		cin >> x >> y;
		v[x].push_back(y);
		v[y].push_back(x);
	}
	color[1] = 1;
	q.push(1);
	while (!q.empty())
	{
		x = q.front();
		q.pop();
		for ( i = 0; i < v[x].size(); i++)
		{
			if (!color[v[x][i]])
			{
				color[v[x][i]] = color[x] + 1;
				q.push(v[x][i]);
			}
		}
	}
	int ind = 0;
	for ( i = 1; i <= n; i++)
	{
		if (color[i] > ma)
		{
			ma = color[i];
			ind = i;
		}
		color[i] = 0;
	}
	color[ind] = 1;
	q.push(ind);
	while (!q.empty())
	{
		x = q.front();
		q.pop();
		for (i = 0; i < v[x].size(); i++)
		{
			if (!color[v[x][i]])
			{
				color[v[x][i]] = color[x] + 1;
				q.push(v[x][i]);
			}
		}
	}
	ma = 0;
	for (i = 1; i <= n; i++)
	{
		ma = max(ma, color[i]);
		color[i] = 0;
	}
	for ( j = 1; j <= n; j++)
	{
		c[j] = 1;
		color[j] = 1;
		q.push(j);
		while (!q.empty())
		{
			x = q.front();
			q.pop();
			for (i = 0; i < v[x].size(); i++)
			{
				if (c[v[x][i]] == 0 || c[v[x][i]] == c[x] + 1)
				{
					color[v[x][i]] += color[x];
				}
				if (!c[v[x][i]])
				{
					c[v[x][i]] = c[x] + 1;
					q.push(v[x][i]);
				}
			}
		}
		for ( i = 1; i <= n; i++)
		{
			if (c[i] == ma)
			{
				ans += color[i];
			}
			c[i] = 0;
			color[i] = 0;
		}
	}
	cout << ans/2;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	int tt = 1;
	//cin >> tt;
	while (tt--)
	{
		solve();
	}
	return 0;
}

Compilation message (stderr)

shymbulak.cpp: In function 'void solve()':
shymbulak.cpp:38:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |   for ( i = 0; i < v[x].size(); i++)
      |                ~~^~~~~~~~~~~~~
shymbulak.cpp:63:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |   for (i = 0; i < v[x].size(); i++)
      |               ~~^~~~~~~~~~~~~
shymbulak.cpp:87:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |    for (i = 0; i < v[x].size(); i++)
      |                ~~^~~~~~~~~~~~~
shymbulak.cpp:24:18: warning: unused variable 'oo' [-Wunused-variable]
   24 |  int i, j, x, y, oo = 1000000000;
      |                  ^~

• Subtask 1: 0 / 30
• Subtask 2: 0 / 20
• Subtask 3: 0 / 50