#include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int read()
{
	int x,f=1;
	char ch;
	while(ch=getchar(),!isdigit(ch))if(ch=='-')f=-1;
	x=ch-48;
	while(ch=getchar(),isdigit(ch))x=x*10+ch-48;
	return x*f;
}
void write(int x)
{
	if(x<0)putchar('-'),x=-x;
	int cnt=0;char ch[50];
	while(ch[++cnt]=x%10+48,x/=10);
	while(putchar(ch[cnt]),--cnt);
	putchar('\n');
}
#define maxe 101000
#define maxn 40100
int rt[maxn];
struct edge
{
	int f,t,d;
}a[maxe];
int len;
void insert(int x,int y,int z)
{
	a[++len].t=y;a[len].f=x;a[len].d=z;
}
bool com(const edge & a,const edge & b)
{
	return a.d>b.d;
}
int find(int x)
{
	int xx=x,y;
	while(rt[xx]!=xx)xx=rt[xx];
	while(x!=xx)y=rt[x],rt[x]=xx,x=y;
	return xx;
}
int main()
{
	freopen("prison1.in","r",stdin);
	freopen("prison1.out","w",stdout);
	int n=read(),m=read();
	for(int i=1;i<=2*n;i++)rt[i]=i;
	for(int i=1;i<=m;i++)
	{
		int x=read(),y=read(),z=read();
		insert(x,y,z);
	}
	sort(a+1,a+1+m,com);
	for(int i=1;i<=m;i++)
	{
		int fx=find(a[i].f),fy=find(a[i].t),fa=find(a[i].f+n),fb=find(a[i].t+n);//cout<<a[i].d<<endl;
		if(fx==fy/*||fa==fb*/)
		{
			write(a[i].d);
		//	system("pause");
			return 0;
		}
		rt[fa]=fy;
		rt[fb]=fx;
	}
	puts("0");
	//system("pause");
}