#include <bits/stdc++.h> using namespace std; // #include <ext/pb_ds/assoc_container.hpp> // #include <ext/pb_ds/tree_policy.hpp> // using namespace __gnu_pbds; typedef long long ll; typedef long double ld; typedef pair<int, int> pii ; typedef pair<ll, ll> pll ; typedef vector<pii> vii ; typedef vector<int> veci ; typedef vector<pll> vll ; typedef vector<ll> vecll; // find_by_order order_of_key #pragma GCC optimize("O3,unroll-loops") #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt") #define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update> #define F first #define S second #define pb push_back #define endl '\n' #define Mp make_pair #define all(x) x.begin(), x.end() #define debug(x) cerr << #x << " = " << x << endl #define set_dec(x) cout << fixed << setprecision(x); #define fast_io ios::sync_with_stdio(false);cin.tie(0);cout.tie(0); #define file_io freopen("in.txt" , "r" , stdin) ; freopen("out.txt" , "w" , stdout); #define lb lower_bound #define ub upper_bound #define for1(n) for(int i=1;i<=n;i++) #define for0(n) for(int i=0;i<n;i++) #define forn(n) for(int i=n;i>0;i--) #define pq priority_queue <int, vector<int>, greater<int>> const int N=3e3+3; int n,m,k,q; vector<int>g[N]; bool check(int t,int x){ int tt=t; multiset<int>C; pq D; for1(n){ while(C.size() && (*C.begin())==i) C.erase(C.begin()); while(D.size() && D.top()==i) D.pop(); for(int x:g[i])C.insert(x); while(t+int(C.size())-int(D.size())>x){ auto it=C.end();it--; D.push((*it)); C.erase(it); tt--; if(tt<0)return 0; } } return 1; } int solve(int x){ for(int t=1;t<=x;t++)if(check(t,x))return 1; return 0; } int main(){ fast_io cin>>n>>m; for1(m){ int a,b,c;cin>>a>>b>>c; if(a>b)swap(a,b); g[a].pb(b); } int l=0,r=m; while(r-l!=1){ int mid=(l+r)>>1; if(solve(mid)==0)l=mid; else r=mid; } cout<<l+1<<endl; }