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 <cstdio>
#include <vector>
#include <algorithm>
using namespace std;

int root[10005];
int findR(int a){
    if(root[a] != a)
        root[a] = findR(root[a]);
    return root[a];
}
class edge{
public:
    int sp, ep, w;
    edge(){}
};
bool cmp(const edge& A, const edge& B){
    return A.w < B.w;
}
vector<edge> vec;

int main(){
    int v, e;
    scanf("%d%d", &v, &e);
    vec.resize(e);
    for(int i = 0; i < e; ++i)
        scanf("%d%d%d", &vec[i].sp, &vec[i].ep, &vec[i].w);
    sort(vec.begin(), vec.end(), cmp);
    int sum = 0, cnt = 0;
    for(int i = 0; i < v; ++i)
        root[i] = i;
    for(int i = 0; i < e && cnt < v-1; ++i){
        int sp = vec[i].sp, ep = vec[i].ep, w = vec[i].w;
        int rSP = findR(sp), rEP = findR(ep);
        if(rSP != rEP){
            sum+=w;
            root[rEP] = rSP;
            cnt++;
        }
    }
    printf("%d\n", sum);
    return 0;
}