static void Main(string[] args)
{
var sets = new DisjointSets <int>();
var edges = new SortedDictionary <Tuple <int, int, int>, Tuple <int, int> >();
var mn = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
var k = 0;
for (int i = 0; i < mn[1]; ++i)
{
var xyr = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();
edges.Add(Tuple.Create(xyr[2], xyr[0] + xyr[1] + xyr[2], k++), Tuple.Create(xyr[0], xyr[1]));
}
var w = 0;
foreach (var e in edges)
{
var xs = sets.MakeSet(e.Value.Item1);
var ys = sets.MakeSet(e.Value.Item2);
if (xs != ys) // Not yet connected
{
w += e.Key.Item1;
sets.Union(xs, ys);
}
}
Console.WriteLine(w);
}
public Node(DisjointSets <T> owner, T value)
{
this.owner = owner;
this.value = value;
this.parent = this;
this.rank = 0;
this.count = 1;
}
