#include <bits/stdc++.h> using namespace std; using ll = long long; using ld = long double; #define all(s) (s).begin(),(s).end() #define vcin(n) for(ll i=0;i<ll(n.size());i++) cin>>n[i] #define rever(vec) reverse(vec.begin(), vec.end()) #define sor(vec) sort(vec.begin(), vec.end()) #define fi first #define se second const ll mod = 998244353; //const ll mod = 1000000007; const ll inf = 2000000000000000000ll; static const long double pi = 3.141592653589793; template<class T,class U> void chmax(T& t,const U& u){if(t<u) t=u;} template<class T,class U> void chmin(T& t,const U& u){if(t>u) t=u;} ll modPow(ll a, ll n, ll mod) { ll ret = 1; ll p = a % mod; while (n) { if (n & 1) ret = ret * p % mod; p = p * p % mod; n >>= 1; } return ret; } class UnionFind{ public: vector<ll> par; vector<ll> siz; UnionFind(ll sz_):par(sz_),siz(sz_,1ll){ for(int i=0;i<sz_;i++) par[i]=i; } void init(ll sz_){ par.resize(sz_); siz.assign(sz_,1ll); for(int i=0;i<sz_;i++) par[i]=i; } ll root(ll x){ while(par[x]!=x){ x=par[x]=par[par[x]]; } return x; } bool merge(ll x,ll y){ x=root(x); y=root(y); if(x==y) return false; if(siz[x]<siz[y]) swap(x,y); siz[x]+=siz[y]; par[y]=x; return true; } bool issame(ll x,ll y){ return root(x)==root(y); } ll size(ll x){ return siz[root(x)]; } }; int main() { /* mod は 1e9+7 */ ios::sync_with_stdio(false); std::cin.tie(nullptr); cout<< fixed << setprecision(10); ll n,m; cin>>n>>m; UnionFind t(n); for(int i=0;i<m;i++){ ll a,b,c; cin>>a>>b>>c; a--; b--; t.merge(a,b); } ll f=t.root(0); ll ans=0; for(int i=0;i<n;i++){ if(f!=t.root(i)){ ans++; } } assert(ans==0); }