#include <bits/stdc++.h>
#define For(i,l,r) for(int i=l; i<=r; i++)
#define per(i,r,l) for(int i=r; i>=l; i--)
#define IOS {cin.tie(0);cout.tie(0);ios::sync_with_stdio(0);}
#define pb push_back
using namespace std;
int fa[2005];
struct node{
    int x,y,w;
}a[2005];
int find(int x){return fa[x]==x?x:fa[x]=find(fa[x]);}
int mi[2005],ma[2005],cnt;
int merge(int id){
    int x=a[id].x,y=a[id].y;
    if (find(x)!=find(y)){
        fa[fa[x]]=fa[y]; return 1;//--cnt;
    }
    return 0;
}
int main(){
    int n,m; cin>>n>>m;
    For(i,1,m) cin>>a[i].x>>a[i].y>>a[i].w;
    For(now,0,n){
        //mi
        cnt=n-1;
        For(j,1,n) fa[j]=j;
        For(i,1,m) if (a[i].w>now) cnt-=merge(i);
        mi[now]=max(now+1,cnt);
        //ma
        cnt=0;
        For(j,1,n) fa[j]=j;
        For(i,1,m) if (a[i].w<=now) cnt+=merge(i);
        ma[now]=cnt;
        //cout<<mi[now]<<' '<<ma[now]<<endl;
    }
if (!ma[0])  printf("0\n"),exit(0);
    For(now,1,n){
        if (ma[now]<now+1||ma[now]<=mi[now-1]) printf("%d\n",now),exit(0);
    }
    printf("%d\n",n+1);
    return 0;
}