#include <iostream>
#include <algorithm>

using namespace std;

const int N = 3010,M = 100010;

int n,m;
int p[N],res[N];

int find(int x)
{
    if(x!=p[x]) p[x]=find(p[x]);
    return p[x];
}

int main()
{
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        for(int i=1;i<=n;i++)
        {
            p[i]=i;
            res[i]=0;
        }
        int u,v,ans=1;
        while(m--)
        {
            int a,b,c;
            cin>>a>>b>>c;
            if(a==b) continue;
            u=find(a),v=find(b);
            res[a]+=c,res[b]+=c;
            if(u!=v)
            {
                ans++;
                p[u]=v; 
            }
        }
        if(ans==n)
        {
            sort(res+1,res+n+1);
            printf("%d\n",res[1]);
        }
    }
}