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#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N = 510, M = 10010;
int n, m;
struct Edge {
int a, b, w;
bool f;
bool operator<(const Edge &t) const {
return w < t.w;
}
} edge[M];
int p[N];
int dist1[N][N], dist2[N][N];
int h[N], e[N * 2], w[N * 2], ne[N * 2], idx;
void add(int a, int b, int c) {
e[idx] = b, w[idx] = c, ne[idx] = h[a], h[a] = idx++;
}
int find(int x) {
if (x == p[x]) return x;
return p[x] = find(p[x]);
}
void dfs(int u, int fa, int maxd1, int maxd2, int d1[], int d2[]) {
d1[u] = maxd1, d2[u] = maxd2;
for (int i = h[u]; ~i; i = ne[i]) {
int j = e[i];
if (j != fa) {
int td1 = maxd1, td2 = maxd2;
if (w[i] > td1)
td2 = td1, td1 = w[i];
else if (w[i] < td1 && w[i] > td2)
td2 = w[i];
dfs(j, u, td1, td2, d1, d2);
}
}
}
int main() {
scanf("%d%d", &n, &m);
memset(h, -1, sizeof h);
for (int i = 0; i < m; i++) {
int a, b, w;
scanf("%d%d%d", &a, &b, &w);
edge[i] = {a, b, w};
}
sort(edge, edge + m);
for (int i = 1; i <= n; i++) p[i] = i;
LL sum = 0;
for (int i = 0; i < m; i++) {
int a = edge[i].a, b = edge[i].b, w = edge[i].w;
int pa = find(a), pb = find(b);
if (pa != pb) {
p[pa] = pb;
sum += w;
add(a, b, w), add(b, a, w);
edge[i].f = true;
}
}
for (int i = 1; i <= n; i++) dfs(i, -1, -1e9, -1e9, dist1[i], dist2[i]);
LL res = 1e18;
for (int i = 0; i < m; i++)
if (!edge[i].f) {
int a = edge[i].a, b = edge[i].b, w = edge[i].w;
LL t;
if (w > dist1[a][b])
t = sum + w - dist1[a][b];
else if (w > dist2[a][b])
t = sum + w - dist2[a][b];
res = min(res, t);
}
printf("%lld\n", res);
return 0;
}