#include using namespace std; #define rep(i,a,b) for(int i=(int)(a);i<(int)(b);i++) #define ALL(v) (v).begin(),(v).end() using ll=long long int; const int inf = 0x3fffffff; const ll INF = 0x1fffffffffffffff; const double eps=1e-12; templateinline bool chmax(T& a,T b){if(ainline bool chmin(T& a,T b){if(a>b){a=b;return 1;}return 0;} templatestruct fp { int v; static int get_mod(){return mod;} int inv() const{ int tmp,a=v,b=mod,x=1,y=0; while(b)tmp=a/b,a-=tmp*b,swap(a,b),x-=tmp*y,swap(x,y); if(x<0){x+=mod;} return x; } fp(ll x=0){init(x%mod+mod);} fp& init(int x){v=(x>=1;} return res;} fp& operator+=(const fp& x){return init(v+x.v);} fp& operator-=(const fp& x){return init(v+mod-x.v);} fp& operator*=(const fp& x){v=ll(v)*x.v%mod; return *this;} fp& operator/=(const fp& x){v=ll(v)*x.inv()%mod; return *this;} fp operator+(const fp& x)const{return fp(*this)+=x;} fp operator-(const fp& x)const{return fp(*this)-=x;} fp operator*(const fp& x)const{return fp(*this)*=x;} fp operator/(const fp& x)const{return fp(*this)/=x;} bool operator==(const fp& x)const{return v==x.v;} bool operator!=(const fp& x)const{return v!=x.v;} friend istream& operator>>(istream& is,fp& x){return is>>x.v;} friend ostream& operator<<(ostream& os,const fp& x){return os<; templatestruct factorial { vector Fact,Finv,Inv; factorial(int maxx){ Fact.resize(maxx); Finv.resize(maxx); Inv.resize(maxx); Fact[0]=Fact[1]=Finv[0]=Finv[1]=Inv[1]=1; rep(i,2,maxx){Fact[i]=Fact[i-1]*i;} Finv[maxx-1]=Fact[maxx-1].inv(); for(int i=maxx-1;i>=2;i--){Finv[i-1]=Finv[i]*i; Inv[i]=Finv[i]*Fact[i-1];} } T fact(int n,bool inv=0){if(n<0)return 0; return (inv?Finv[n]:Fact[n]);} T inv(int n){if(n<0)return 0; return Inv[n];} T nPr(int n,int r,bool inv=0){if(n<0||nstruct matrix{ int h,w; vector> val; T det; matrix(){} matrix(int n,int m):h(n),w(m),val(vector>(n,vector(m))){} vector& operator[](const int i){return val[i];} matrix& operator+=(const matrix& m){ rep(i,0,h)rep(j,0,w)val[i][j]+=m.val[i][j]; return *this; } matrix& operator-=(const matrix& m){ rep(i,0,h)rep(j,0,w)val[i][j]-=m.val[i][j]; return *this; } matrix& operator*=(const matrix& m){ matrix res(h,m.w); rep(i,0,h)rep(j,0,m.w)rep(k,0,w)res.val[i][j]+=val[i][k]*m.val[k][j]; *this=res; return *this; } matrix operator+(const matrix& m)const{return matrix(*this)+=m;} matrix operator-(const matrix& m)const{return matrix(*this)-=m;} matrix operator*(const matrix& m)const{return matrix(*this)*=m;} matrix pow(ll k){ matrix res(h,h),c=*this; rep(i,0,h)res.val[i][i]=1; while(k){if(k&1)res*=c; c*=c; k>>=1;} return res; } vector gauss(int c=-1){ if(val.empty())return {}; if(c==-1)c=w; int cur=0; vector res; det=1; rep(i,0,c){ if(cur==h)break; rep(j,cur,h)if(val[j][i]!=0){ swap(val[cur],val[j]); if(cur!=j)det*=-1; break; } det*=val[cur][i]; if(val[cur][i]==0)continue; rep(j,0,h)if(j!=cur){ T z=val[j][i]/val[cur][i]; rep(k,i,w)val[j][k]-=val[cur][k]*z; } res.push_back(i); cur++; } return res; } friend istream& operator>>(istream& is,matrix& m){ rep(i,0,m.h)rep(j,0,m.w)is>>m[i][j]; return is; } friend ostream& operator<<(ostream& os,matrix& m){ rep(i,0,m.h){ rep(j,0,m.w)os<>8)); } }; int main(){ int n,m; cin>>n>>m; XorShift rnd; matrix m1(n,n); rep(_,0,m){ int x,y,z; cin>>x>>y>>z; x--; y--; z--; unsigned val=rnd.run(); m1[x][y]+=val; m1[y][z]+=val; m1[z][x]+=val; m1[x][z]-=val; m1[y][x]-=val; m1[z][y]-=val; } auto ret=m1.gauss().size()/2; cout<