#include <bits/stdc++.h>
using namespace std;
const int N = 110, M = 210;
int n, m, fa[N];

//结构体
struct Edge {
    int a, b, w;
    bool operator<(const Edge &t) {
        return w < t.w;
    }
} e[M];

//并查集
int find(int x) {
    if (fa[x] != x) fa[x] = find(fa[x]); //路径压缩
    return fa[x];
}
int main() {
    cin >> n >> m;

    //并查集初始化
    for (int i = 1; i <= n; i++) fa[i] = i;

    // Kruskal算法直接记录结构体
    for (int i = 0; i < m; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        e[i] = {a, b, c};
    }
    sort(e, e + m); //不要忘记e数组的长度是边的数量

    int res = 0;
    //枚举每条边
    for (int i = 0; i < m; i++) {
        int a = find(e[i].a), b = find(e[i].b), c = e[i].w;
        if (a != b)
            fa[a] = b;
        else
            res += c; //去掉的边权
    }
    printf("%d\n", res);
    return 0;
}