#include <cstdio>
using namespace std;
 
const int MAXINT=1000000000;
int ava=0,ptow[501],way[124751],wayright[124751],waynext[124751];
 
void addway(int x,int y,int right)
{
	int pos;
	pos=ptow[x];
	if (pos==-1)
	{
		ptow[x]=ava;
		way[ava]=y;
		waynext[ava]=-1;
		wayright[ava++]=right;
	}
	else
	{
		while (waynext[pos]!=-1)
			pos=waynext[pos];
		way[ava]=y;
		waynext[pos]=ava;
		waynext[ava]=-1;
		wayright[ava++]=right;
	}
}
 
int cal(int pos)
{
	int right=0;
	pos=ptow[pos];
	while (pos!=-1)
	{
		right+=wayright[pos];
		pos=waynext[pos];
	}
	return(right);
}
 
int main(void)
{
	freopen("t2bb.in","r",stdin);
	freopen("t2bb.out","w",stdout);
	int i,n,m,x,y,right,temp,minright=MAXINT;
	scanf("%d%d",&n,&m);
	for (i=0;i<n;i++)
		ptow[i]=-1;
	for (i=0;i<m;i++)
	{
		scanf("%d%d%d",&x,&y,&right);
		addway(x,y,right);
		addway(y,x,right);
	}
	for (i=0;i<n;i++)
	{
		temp=cal(i);
		if (minright>temp)
			minright=temp;
	}
	printf("%d\n",minright);
	return(0);
}