#include <stdio.h>
#include <string.h>
#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <time.h>

using namespace std;
typedef long long LL;
const int maxn  = 3333;
const int MOD   = 1e9+7;
const LL inf   = 0x3f3f3f3f;
const double eps= 1e-8;
const double pi = acos(-1.0);
int n,m,t,tot,cnt,ret,ans,tmp;
inline int read()
{
    int  c=0,f=1;
    char ch=getchar();
    while(ch<'0'||ch>'9')
    {
        if(ch=='-')f=-1;
        ch=getchar();
    }
    while(ch>='0'&&ch<='9')
    {
        c=c*10+ch-'0';
        ch=getchar();
    }
    return c*f;
}
int fa[maxn],du[maxn];
int find(int x)//
{
    if(x==fa[x]) return x;
    return fa[x]=find(fa[x]);
}
void init()
{
    for(int i=1; i<=n; ++i) fa[i]=i,du[i]=0;
}
int main()
{
    //freopen("in.txt","r",stdin);
    while(~scanf("%d%d",&n,&m))
    {
        init();
        tot=0;//不连通
        for(int i=1; i<=m; ++i)
        {
            int u,v,w;
            u=read();v=read();w=read();
            if(u==v) continue;
            du[u]+=w;
            du[v]+=w;
            if(find(u)!=find(v))
            {
                ++tot;
               // fa[u]=fa[v];
               fa[find(u)]=find(v);
            }
        }
        if(tot!=n-1)//图本身不连通
        {
            puts("0");
            continue;
        }
        ret=du[1];
        for(int i=2; i<=n; ++i) ret=min(du[i],ret);
        printf("%d\n",ret);
    }
    return 0;
}