#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;

#ifdef WAIMAI
#define debug(HEHE...) cout<<"["<<#HEHE<<"] : ",dout(HEHE)
void dout(){cout<<'\n';}
template<typename T,typename...U>
void dout(T t,U...u){cout<<t<<(sizeof...(u)?", ":""),dout(u...);}
#else
#define debug(...) 7122
#endif

#define int long long
#define ll long long
#define Waimai ios::sync_with_stdio(false),cin.tie(0)
#define FOR(x,a,b) for(int x=a,I=b;x<=I;x++)
#define pb emplace_back
#define F first
#define S second

const int SIZE = 1e4 + 5;
const int MSIZ = 5e5 + 5;

int n, m, cc;
tuple<int, int, int> e[MSIZ];
int to[SIZE], h[SIZE];
bool is[MSIZ];

int dsu (int x) {
    return x == to[x] ? x : (to[x] = dsu (to[x]));
}

bool Merge (int a, int b) {
    a = dsu (a), b = dsu (b);
    if (a == b) return 0;
    if (h[a] < h[b]) swap (a, b);
    to[b] = a;
    h[a] += h[b];
    return 1;
}

void solve() {
    cin >> n >> m;
    FOR (i, 1, m) {
        auto &[w, a, b] = e[i];
        cin >> a >> b >> w;
    }
    sort (e + 1, e + m + 1);

    cc = n;
    iota (to, to + n + 1, 0);
    fill (h, h + n + 1, 1);
    int start;
    for (int i = m; i >= 1; i--) {
        auto [w, a, b] = e[i];
        if (Merge (a, b)) cc--;
        if (cc == 1) {
            start = i;
            break;
        }
    }

    iota (to, to + n + 1, 0);
    fill (h, h + n + 1, 1);
    FOR (i, start, m) {
        auto [w, a, b] = e[i];
        is[i] = Merge (a, b);
    }

    int ans = 0;
    iota (to, to + n + 1, 0);
    fill (h, h + n + 1, 1);
    for (int i = m; i >= 1; i--) if (is[i]) {
        auto [w, a, b] = e[i];
        a = dsu (a), b = dsu (b);
        ans += w * h[a] * h[b];
        Merge (a, b);
    }
    cout << ans << '\n';
}

int32_t main() {
    Waimai;
	solve();
}