#include <bits/stdc++.h>
#define For(i,l,r) for (register int i=l; i<=r; i++)
using namespace std;
typedef unsigned long long LL;
typedef signed long long ll;
template <typename T>
inline void read(T &x) {
    char c = getchar(); int w = 1; x = 0;
    while (!isdigit(c))
        (c == '-') && (w = -w), c = getchar();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ '0'), c = getchar();
    x *= w;
}

const int N = 100010;
int n, m, u, v, w, head[N], cnt = 0;
bool vis[N];
struct Edge {
    int to, w, nxt;
} edge[N<<1];
inline void add(int u, int v, int val) {
    edge[++ cnt].to = v;
    edge[cnt].w = val;
    edge[cnt].nxt = head[u];
    head[u] = cnt;
}
signed main() {
    while (cin >> n >> m) {
        cnt = 0;
        for (register int i=1; i<=n; ++i) {
            head[i] = 0; vis[i] = false;
        }
        for (register int i=1; i<=m; ++i) {
            read(u); read(v); read(w);
            if (u == v) continue;
            add(u, v, w);
            add(v, u, w);
        }
        queue<int> q;
        q.push(1);
        vis[1] = true;
        while (!q.empty()) {
            int fr = q.front(); q.pop();
            for (register int i=head[fr]; i; i=edge[i].nxt) {
                int to = edge[i].to;
                if (!vis[to]) {
                    vis[to] = true; q.push(to);
                }
            }
        }
        bool flag = true;
        for (register int i=1; i<=n; ++i) {
            if (!vis[i]) {
                flag = false; break;
            }
        }
        if (!flag) {
            puts("0"); continue;
        }
        int ans = 100000000;
        for (register int i=1; i<=n; ++i) {
            int res = 0;
            for (register int j=head[i]; j; j=edge[j].nxt) {
                res += edge[j].w;
            }
            ans = min(ans, res);
        }
        printf("%d\n", ans);
    }
    getchar();
    return 0;
}