public static void LearningLanguages()
{
var nm = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
var n = nm[0];
var k = nm[1];
var dj = new DisjointSet(n + 1);
var languages = new Dictionary <int, List <int> >();
var noLang = 0;
for (int i = 0; i < n; i++)
{
var employee = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
if (employee[0] == 0)
{
noLang++;
}
for (int j = 1; j < employee.Length; j++)
{
if (languages.ContainsKey(employee[j]))
{
languages[employee[j]].Add(i);
}
else
{
languages.Add(employee[j], new List <int> {
i
});
}
}
}
var amount = n;
for (int i = 1; i <= k; i++)
{
if (!languages.ContainsKey(i))
{
continue;
}
for (int j = 0; j < languages[i].Count && j + 1 < languages[i].Count; j++)
{
if (dj.Union(languages[i][j], languages[i][j + 1]))
{
amount--;
}
}
}
if (noLang == n)
{
amount++;
}
Console.WriteLine(amount - 1);
}
public static void NonYekaterinburgSubway()
{
var nkm = Console.ReadLine().Split(' ').Select(Int32.Parse).ToArray();
var n = nkm[0];
var k = nkm[1];
var m = nkm[2];
var dj = new DisjointSet(n);
for (int i = 0; i < k; i++)
{
var xy = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
dj.Union(xy[0], xy[1]);
}
for (int i = 0; i < m; i++)
{
var xy = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
}
Console.WriteLine(dj.SetCount - 1);
}
static void BearAndFriendshipCondition()
{
var nm = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
var n = nm[0];
var m = nm[1];
var dj = new DisjointSet(n);
var graph = new Dictionary <int, List <int> >();
for (int i = 0; i < m; i++)
{
var input = Console.ReadLine().Split().Select(Int32.Parse).ToArray();
dj.Union(input[0], input[1]);
try
{
graph[input[0]].Add(input[1]);
}
catch (Exception e)
{
graph.Add(input[0], new List <int> {
input[1]
});
}
try
{
graph[input[1]].Add(input[0]);
}
catch (Exception e)
{
graph.Add(input[1], new List <int> {
input[0]
});
}
//if (graph.ContainsKey(input[0]))
// graph[input[0]].Add(input[1]);
//else graph.Add(input[0], new List<int> { input[1] });
//if (graph.ContainsKey(input[1]))
// graph[input[1]].Add(input[0]);
//else graph.Add(input[1], new List<int> { input[0] });
}
var parents = new Dictionary <int, List <int> >();
for (int i = 1; i <= n; i++)
{
var p = dj.FindRepresentative(i);
try
{
parents[p].Add(i);
}
catch (Exception e)
{
parents.Add(p, new List <int> {
i
});
}
//if (parents.ContainsKey(p))
// parents[p].Add(i);
//else parents.Add(p, new List<int> { i });
}
foreach (var g in graph)
{
if (!parents.ContainsKey(g.Key) || parents[g.Key].Count <= 0)
{
continue;
}
var degree = parents[g.Key].Where(p => graph.ContainsKey(p)).Sum(p => graph[p].Count);
var k = parents[g.Key].Count;
k = k * (k - 1) / 2;
if (k == degree / 2)
{
continue;
}
Console.WriteLine("NO");
return;
}
Console.WriteLine("YES");
}