#include //ios::sync_with_stdio(false);cin.tie(0);cout.tie(0); //clock_t start=clock();clock_t end=clock();cout<<(double)(end-start)/CLOCKS_PER_SEC< pii; typedef pair ppii; typedef pair pipi; typedef pair pll; typedef pair ppll; typedef pair plpl; typedef pair P; typedef tuple tl; typedef pair pdd; typedef vector> mat; ll mod=1000000007; ll mod2=998244353; ll mod3=1000003; ll mod4=998244853; ll mod5=1000000009; ll inf=1LL<<60; double pi=3.141592653589793238462643383279L; double eps=1e-14; #define rep(i,m,n) for(ll i=m;i=m;i--) #define srep(itr,st) for(auto itr=st.begin();itr!=st.end();itr++) #define mrep(itr,mp) for(auto itr=mp.begin();itr!=mp.end();itr++) #define Max(a,b) a=max(a,b) #define Min(a,b) a=min(a,b) int dh[4]={1,-1,0,0}; int dw[4]={0,0,1,-1}; int ddh[8]={-1,-1,-1,0,0,1,1,1}; int ddw[8]={-1,0,1,-1,1,-1,0,1}; struct custom_hash { static uint64_t splitmix64(uint64_t x) { // http://xorshift.di.unimi.it/splitmix64.c x += 0x9e3779b97f4a7c15; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31); } size_t operator()(uint64_t x) const { static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count(); return splitmix64(x + FIXED_RANDOM); } }; #define umh unordered_map ll gcd(ll a,ll b){ if(a0){ if(k&1)ret*=now; now*=now; k/=2; } return ret; } ll beki(ll n,ll k,ll md){ ll ret=1; ll now=n; now%=md; while(k>0){ if(k%2==1){ ret*=now; ret%=md; } now*=now; now%=md; k/=2; } return ret; } ll gyaku(ll n,ll md){ return beki(n,md-2,md); } ll popcount(ll n){ ll ret=0; ll u=n; while(u>0){ ret+=u%2; u/=2; } return ret; } bool used[100001],used2[100001]; vector v[100001],w[100001],vc[100001]; bool dfs(int now,int par,int c){ bool ret=false; if(c==1){ rep(i,0,v[now].size()){ int ne=v[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,1); if(ret)break; used[ne]=false; used2[ne]=true; } rep(i,0,vc[now].size()){ int ne=vc[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,1); if(ret)break; used[ne]=false; used2[ne]=true; } } else if(c==0){ rep(i,0,vc[now].size()){ int ne=vc[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,0); if(ret)break; used[ne]=false; used2[ne]=true; } rep(i,0,v[now].size()){ int ne=v[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,1); if(ret)break; used[ne]=false; used2[ne]=true; } rep(i,0,w[now].size()){ int ne=w[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,2); if(ret)break; used[ne]=false; used2[ne]=true; } } else if(c==2){ rep(i,0,w[now].size()){ int ne=w[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,2); if(ret)break; used[ne]=false; used2[ne]=true; } rep(i,0,vc[now].size()){ int ne=vc[now][i]; if(par==ne)continue; if(used[ne]){ return true; } if(used2[ne])continue; used[ne]=true; ret=dfs(ne,now,2); if(ret)break; used[ne]=false; used2[ne]=true; } } return ret; } int main(){ ios::sync_with_stdio(false);cin.tie(0); int n,m;cin>>n>>m; map mp,mp2; int win=0; rep(i,0,m){ int a,b,c;cin>>a>>b>>c; a--; b--; if(c==1){ if(a>b)swap(a,b); mp[{a,b}]++; if(mp[{a,b}]>=2||(mp[{a,b}]==1&&(mp2[{a,b}]>=1||mp2[{b,a}]>=1)))win=1; } else{ mp2[{a,b}]++; if(mp2[{a,b}]>=1&&mp2[{b,a}]>=1)win=1; if((mp[{min(b,a),max(a,b)}]>=1&&(mp2[{a,b}]>=1||mp2[{b,a}]>=1)))win=1; } if(c==1){ vc[a].push_back(b); vc[b].push_back(a); } else{ v[a].push_back(b); w[b].push_back(a); } } if(win){ cout<<"Yes"<