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

int n, m;
int i, j;
vector<long long> p(n);

void make_set(){
        for(i = 0; i < n; i++){
                p[i] = i;
        }
}

int get_parent(long long v){
        return (v == p[v]) ? v : (p[v] = get_parent(p[v]));
}

void unite(long long a, long long b){
        a = get_parent(a);
        b = get_parent(b);
        swap(a, b);
        if(a != b){
                p[a] = b;
        }
}

int main() {
        // your code goes here
        cin >>n >>m;
        long long sum = 0;

        p.assign(n, 0);
        make_set();
        /*for(i = 0; i < n; i++){
                cout <<p[i] <<' ';
        }
        cout <<endl;*/

        vector < pair < long long, pair<long long, long long> > > g; // вес - вершина 1 - вершина 2
        for (i = 0; i < m; i++) {
        long long x, y, z;
        cin >>x >>y >>z;
        x--; y--;
        sum += z;
        z = z * (-1);
        g.push_back(make_pair(z, make_pair(x, y)));
       /* long long a = g[i].second.first,  b = g[i].second.second,  l = g[i].first;
                cout <<a <<' ' <<b <<' ' <<l <<endl;*/
    }

        long long cost = 0;
        vector < pair<long long, long long> > res;

        sort (g.begin(), g.end());

        for (i = 0; i < m; i++) {
                long long a = g[i].second.first,  b = g[i].second.second,  l = g[i].first;
                //cout <<a <<' ' <<b <<' ' <<l <<endl;
                if (get_parent(a) != get_parent(b)) {
                        cost += l;
                        res.push_back (g[i].second);
                        unite (a, b);
                }
        }
        cout <<sum + cost;
        return 0;
}