#1AC后全WA，已知#2答案少了

#include<bits/stdc++.h>
using namespace std;
int father[1000005];
struct node{
	int u,v,cnt;
}a[100005];
bool cmp(node a,node b){
	return a.cnt>b.cnt;
}
int find(int x){
	if(father[x]!=x)father[x]=find(father[x]);
	return father[x];
}
int main(){
//	freopen("1.in","r",stdin); 
	int n,m;
	cin>>n>>m;
	for(int i=1;i<=n*2;i++)father[i]=i;
	for(int i=1;i<=m;i++){
		cin>>a[i].u>>a[i].v>>a[i].cnt;
	}
	sort(a+1,a+n+1,cmp); 
	for(int i=1;i<=m;i++){
		int fu=find(a[i].u),fv=find(a[i].v),ffu=find(a[i].u+n),ffv=find(a[i].v+n);
		if(fu==fv){
			cout<<a[i].cnt;
			return 0;
		}
		father[fu]=ffv;
		father[ffu]=fv;
	}
	cout<<0;
	return 0;
}
//4 4
//1 2 100000
//3 4 100000
//1 3 2
//2 4 1