#include<iostream>
#include<fstream>
#include<iomanip>
#include<stdio.h>
#include<cstdio>
#include<math.h>
#include<cmath>
#include<algorithm>
#include<string>
#include<cstring>
#include<string.h>
#include<vector>
#include<stack>
#include<queue>
#include<map>
#include<set>
#include<cstdlib>
#include<stdlib.h>
#include<ctime>
#include<time.h>
using namespace std;
#define LL long long
const int N=1e5+5;
const LL INF=0x3f3f3fff3f3f3f;
struct node{
	LL x,y,z;
}p[N],t[N];
LL fa[N],len,n,m;
void init(){
	for(int i=0;i<=n;i++){
		fa[i]=i;
	}
} 
bool cmp(node a,node b){
	if(a.z!=b.z){
		return a.z<b.z;
	}
	if(a.x!=b.x){
		return a.x<b.x;
	}
	return a.y<b.y;
}
int find(int x){
	if(fa[x]==x){
		return x;
	}
	fa[x]=find(fa[x]);
	return fa[x];
}
LL kruskal1(){
	LL num=0,sum=0;
	for(int i=0;i<m;i++){
		int x=p[i].x;
		int y=p[i].y;
		x=find(x);
		y=find(y);
		if(x!=y){
			fa[x]=y;
			num++;
			t[len].x=p[i].x;
			t[len].y=p[i].y;
			t[len].z=p[i].z;
			len++;
			sum+=p[i].z;
			if(num==n-1){
				return sum;
			}
		}
	}
	return INF;
}
LL kruskal2(LL xx,LL yy,LL zz){
	LL num=0,sum=0;
	for(int i=0;i<m;i++){
		LL x=p[i].x;
		LL y=p[i].y;
		if(xx==x&&yy==y){
			continue;
		}
		x=find(x);
		y=find(y);
		if(x!=y){
			fa[x]=y;
			num++;
			sum+=p[i].z;
			if(num==n-1){
				return sum;
			}
		}
	}
	return INF;
}
int main(){
	/*
	freopen(".in","r",stdin);
	freopen(".out","w",stdout);
	*/
	cin>>n>>m;
	init();
	for(int i=0;i<m;i++){
		cin>>p[i].x>>p[i].y>>p[i].z;
		if(p[i].x>p[i].y){
			swap(p[i].x,p[i].y);
		}
	}
	sort(p,p+m,cmp);
	LL ans=kruskal1();
	LL sum=INF;
	for(int i=0;i<len;i++){
		init();
		LL num=kruskal2(t[i].x,t[i].y,t[i].z);
		if(num<sum&&num>ans){
			sum=num;
		}
	}
	cout<<sum<<endl;
	return 0;
}

/*****************************************
Note:
******************************************/
#include <queue>
#include <set>
#include <math.h>
#include <stack>
#include <stdio.h>
#include <iostream>
#include <vector>
#include <iomanip>
#include <string.h>
#include <algorithm>
#include <cstdio>
#include <cstring>
using namespace std;
#define LL long long
const int N = 1e6 + 10;
const LL INF = 1e11+1;
struct node{
	LL x,y,z;
}p[N],t[N];
LL fa[N],len,n,m;
void init()
{
	for(int i=0;i<=n;i++)
		fa[i]=i;
}
bool cmp(node a,node b)
{
	if(a.z!=b.z)
		return a.z<b.z;
	if(a.x!=b.x)
		return a.x<b.x;
	return a.y<b.y;
}
int find(int x)
{
	return (fa[x]==x)?x:fa[x]=find(fa[x]);
}
LL kruskal1()
{
	LL num=0,sum=0;
	for(int i=1;i<=m;i++)
	{
		int x=find(p[i].x),y=find(p[i].y);
		if(x!=y)
		{
			fa[x]=y;
			num++;
			t[++len].x=p[i].x;
			t[len].y=p[i].y;
			t[len].z=p[i].z;
			sum+=p[i].z;
			if(num==n-1)
				return sum;
		}
	}
	return INF;
}
LL kruskal2(LL xx,LL yy,LL zz)
{
	LL num=0,sum=0;
	for(int i=1;i<=m;i++)
	{
		if(xx==p[i].x&&yy==p[i].y) continue;
		int x=find(p[i].x),y=find(p[i].y);
		if(x!=y)
		{
			fa[x]=y;
			num++;
			sum+=p[i].z;
			if(num==n-1)
				return sum;
		}
	}
	return INF;
}
int main()
{
	cin>>n>>m;
	init();
	for(int i=1;i<=m;i++)
	{
		cin>>p[i].x>>p[i].y>>p[i].z;
		if(p[i].x>p[i].y)
			swap(p[i].x,p[i].y);
	}
	sort(p+1,p+m+1,cmp);
	LL ans=kruskal1(),sum=INF;
	for(int i=1;i<=len;i++)
	{
		init();
		LL num=kruskal2(t[i].x,t[i].y,t[i].z);
		if(num<sum&&num>ans)
			sum=num;
	}
	cout<<sum<<endl;
	return 0;
}