#include<cstdio>
#include<algorithm>
using namespace std;
const int N=3010;
int n,m,i,x,y,w,g[N],ans,f[N],ret;
int F(int x){return f[x]==x?x:f[x]=F(f[x]);}
int main(){
  while(~scanf("%d%d",&n,&m)){
    for(i=1;i<=n;i++)f[i]=i,g[i]=0;
    ret=n-1;
    while(m--){
      scanf("%d%d%d",&x,&y,&w);
      if(x==y)continue;
      g[x]+=w;
      g[y]+=w;
      if(F(x)!=F(y)){
        f[f[x]]=f[y];
        ret--;
      }
    }
    ans=~0U>>1;
    for(i=1;i<=n;i++)ans=min(ans,g[i]);
    if(ret)ans=0;
    printf("%d\n",ans);
  }
}