Problem: Find the sum of weights of edges of the Minimum Spanning Tree for a given weighted undirected graph G = (V, E).

Constraints

* 1 ≤ |V| ≤ 10,000
* 0 ≤ |E| ≤ 100,000
* 0 ≤ wi ≤ 10,000
* The graph is connected
* There are no parallel edges
* There are no self-loops

Input


|V| |E|
s0 t0 w0
s1 t1 w1
:
s|E|-1 t|E|-1 w|E|-1


, where |V| is the number of vertices and |E| is the number of edges in the graph. The graph vertices are named with the numbers 0, 1,..., |V|-1 respectively.

si and ti represent source and target verticess of i-th edge (undirected) and wi represents the weight of the i-th edge.

Output

Print the sum of the weights of the Minimum Spanning Tree.

Examples

Input

4 6
0 1 2
1 2 1
2 3 1
3 0 1
0 2 3
1 3 5


Output

3


Input

6 9
0 1 1
0 2 3
1 2 1
1 3 7
2 4 1
1 4 3
3 4 1
3 5 1
4 5 6


Output

5

Solution (in CPP):

Solution:
#include<bits/stdc++.h>
using namespace std;
using UL=unsigned int;
using LL=long long;
using ULL=unsigned long long;
#define rep(i,n) for(UL i=0; i<(n); i++)

struct UF{
 UL N; vector<UL> V;
 void init(UL n){
  N=n; V.resize(N);
  rep(i,N) V[i]=i;
 }
 UL root(UL a){
  if(V[a]==a) return a;
  return V[a]=root(V[a]);
 }
 void unite(UL r,UL s){
  V[root(s)] = root(r);
 }
};

struct Edge{ UL u,v; UL w; };
bool wcmp(const Edge& l, const Edge& r){ return l.w<r.w; }

UL N,M;
Edge J[100000];
UF G;
ULL ans = 0;

int main(){
 scanf("%u%u",&N,&M);
 G.init(N);
 rep(i,M){
  UL u,v,w; scanf("%u%u%u",&u,&v,&w);
  J[i]=Edge{u,v,w};
 }
 sort(J,J+M,wcmp);
 rep(i,M){
  if(G.root(J[i].u)==G.root(J[i].v)) continue;
  G.unite(J[i].u,J[i].v);
  ans+=J[i].w;
 }
 printf("%u\n",ans);
 return 0;
}