#include <cstdlib>
#include <cstdio>
#include <vector>
using namespace std;
const int MAXN=555;
vector<int> map[MAXN],val[MAXN];
int N,M,x,y,z,ans=11111111;

inline void init()
{
	scanf("%d %d\n",&N,&M);
	for(int i=1;i<=M;i++)
	{
		scanf("%d %d %d\n",&x,&y,&z);
		x++,y++;
		map[x].push_back(y);
		map[y].push_back(x);
		val[x].push_back(z);
		val[y].push_back(z);
	}
}

inline void cheat()
{
	int res=0;
	for(int i=1;i<=N;i++)
	{
		res=0;
		for(unsigned int j=0;j<map[i].size();j++)
			res+=val[i][j];
		if(res<ans) ans=res;
	}
	printf("%d\n",ans);
}

int main()
{
	freopen("t2bb.in","r",stdin);
	freopen("t2bb.out","w",stdout);
	init();
	cheat();
	return 0;
}