#include <bits/stdc++.h>
#define endl "\n"
using namespace std;
typedef long long ll;
typedef long double ld;
typedef vector<ll> vl;
typedef pair<ll, ll> PP;
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx")
#pragma comment(linker, "/stack:200000000")
#define overload4(_1, _2, _3, _4, name, ...) name
#define overload3(_1, _2, _3, name, ...) name
#define rep1(n) for (ll i = 0; i < n; ++i)
#define rep2(i, n) for (ll i = 0; i < n; ++i)
#define rep3(i, a, b) for (ll i = a; i < b; ++i)
#define rep4(i, a, b, c) for (ll i = a; i < b; i += c)
#define rep(...) overload4(__VA_ARGS__, rep4, rep3, rep2, rep1)(__VA_ARGS__)
#define rrep1(n) for (ll i = n; i--;)
#define rrep2(i, n) for (ll i = n; i--;)
#define rrep3(i, b, a) for (ll i = b; i-- > (a);)
#define rrep4(i, b, a, c) \
  for (ll i = (a) + ((b) - (a)-1) / (c) * (c); i >= (a); i -= c)
#define rrep(...) \
  overload4(__VA_ARGS__, rrep4, rrep3, rrep2, rrep1)(__VA_ARGS__)
#define elif else if
ll beki(ll i)
{
  return 1ll << i;
}
#define all(v) v.begin(), v.end()
#define allm(x, y, M) for (auto [(x), (y)] : (M))
#define alls(i, S) for (auto(&i) : (S))
#define pb push_back
#define fi first
#define se second
#define escape(a) \
  print(a);       \
  return;
const ll INF = (1LL << 61) - 1;
const ll MAX_N1 = 200010;
const ll MAX_N2 = 500010;
ll min(int x, ll y) { return min(ll(x), y); }
ll min(ll x, int y) { return min(x, ll(y)); }
ll max(int x, ll y) { return max(ll(x), y); }
ll max(ll x, int y) { return max(x, ll(y)); }
ld DIV(ll x, ll y) { return ld(x) / ld(y); }
template <class X>
void print(X x) { cout << x << endl; }
template <class X>
void printt(X x) { cout << x; }
void print(vl x)
{
  for (ll i : x)
  {
    cout << i << " ";
  }
  cout << endl;
}
template <class X>
vector<X> ruiseki(vector<X> &A)
{
  vector<X> P;
  P.pb(0);
  for (X i : A)
  {
    P.pb(P.back() + i);
  }
  return P;
}
template <class X>
vector<X> printpart(vector<X> &A, ll x, ll y)
{
  rep(i, x, y + 1) { cout << A[i] << " "; }
  print("");
}
void print(vector<PP> x)
{
  for (PP i : x)
  {
    cout << i.first << " " << i.second << endl;
  }
  cout << endl;
}
template <class X>
int lbound(vector<X> &Y, X a)
{
  return lower_bound(all(Y), a) - Y.begin();
}
template <class X>
int ubound(vector<X> &Y, X a)
{
  return upper_bound(all(Y), a) - Y.begin();
}
template <class X>
X lbound2(vector<X> &Y, X a, int mode = 0)
{
  int x = lbound(Y, a) - mode;
  if (x < 0 || x >= Y.size())
    return INF;
  return Y[x];
}
template <class X>
X ubound2(vector<X> &Y, X a, int mode = 0)
{
  int x = ubound(Y, a) - mode;
  if (x < 0 || x >= Y.size())
    return INF;
  return Y[x];
}
template <class... T>
void cl(T &...t) { (..., (t.clear())); }
template <class... T>
void in(T &...t) { (..., (cin >> t)); }
template <class... T>
void put(vl &V, int n, int mode = 0)
{
  ll k;
  if (mode == 0)
    cl(V);
  rep(i, n)
  {
    cin >> k;
    V.pb(k);
  }
}
int max_index(vl &V) { return max_element(all(V)) - V.begin(); }
int min_index(vl &V) { return min_element(all(V)) - V.begin(); }
ll sum(vl &V) { return accumulate(all(V), 0ll); }
template <typename T>
void UNIQUE(vector<T> &v)
{
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());
}
template <typename T>
T ADD(T a, T b)
{
  T res;
  return __builtin_add_overflow(a, b, &res) ? numeric_limits<T>::max() : res;
}
template <typename T>
T MUL(T a, T b)
{
  T res;
  return __builtin_mul_overflow(a, b, &res) ? numeric_limits<T>::max() : res;
};
template <typename T>
T POW(T a, int n)
{
  T res = 1;
  for (; n > 0; n >>= 1, a *= a)
    if (n & 1)
      res *= a;
  return res;
}
template <class X>
bool ma(X &a, X b)
{
  if (a < b)
  {
    a = b;
    return true;
  }
  return false;
}
template <class X>
bool mi(X &a, X b)
{
  if (a > b)
  {
    a = b;
    return true;
  }
  return false;
}
void vset(vl &A, ll n, ll k) { A = vl(n, k); }
ll divup(ll x, ll y) { return (x + y - 1) / y; }
ll a, b, c, d, e, f, h, x, y, z, p, q, n, t, r, k, w, l, ans, m, u, v;
ll codeforces = 1;
// const ll mod = 1000000007;
const ll mod = 998244353;
vl g[MAX_N2];
vector<PP> VP, VP2;
string S, T, U;
vl A, B, C, D;
class UnionFind
{
  // まとめる 判定 サイズを知る
public:
  // Aから見た親の番号を格納する。rootだったら-1*その集合のサイズ。
  vector<int> Parent;

  // 初期化
  UnionFind(ll N) { Parent = vector<int>(N, -1); }

  // Aのrootを調べる
  int root(int A)
  {
    if (Parent[A] < 0)
      return A; // マイナスならそれはroot
    return Parent[A] = root(Parent[A]);
  }

  // rootの値をプラスに戻して返す(サイズ)
  ll size(int A) { return -Parent[root(A)]; }

  // くっつける関数
  bool connect(int A, int B)
  {
    // AとBのroot同士をくっつける
    A = root(A); // ここのAは、"rootの場所"の意味
    B = root(B);
    if (A == B)
      return false; // 既にくっついている
    if (size(A) < size(B))
      swap(A, B);           // 大きい方にくっつけるために中身交換
    Parent[A] += Parent[B]; // 中身更新
    Parent[B] = A;
    return true;
  }
};
void solve()
{
  in(n, m);
  UnionFind uni(n);
  vector<tuple<ll, ll, ll>> VT;
  rep(m)
  {
    in(x, y, z);
    x--;
    y--;
    VT.pb({z, x, y});
  }
  sort(all(VT));
  rep(i, m)
  {
    auto [z, x, y] = VT[i];
    p = uni.size(x);
    q = uni.size(y);
    if (uni.connect(x, y))
    {
      ans += p * q * z;
    }
  }
  print(ans);
}
int main()
{
  cout << fixed << setprecision(15);
  cin.tie(0);
  ios::sync_with_stdio(false);
  // cin >> codeforces;
  rep(i, codeforces)
  {
    ans = 0;
    solve();
  }
}