#pragma GCC optimize("O2") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define whlie while #define retunr return #define reutrn return #define reutnr return #define mp make_pair #define pb push_back #define eb emplace_back #define fi first #define se second #define inf 1001001001 #define infLL (1LL << 61) #define FOR(i,a,b) for(int (i)=(int)(a); (i)<(int)(b); (i)++) // [a,b) #define rep(i,N) FOR((i), 0, (int)(N)) // [0,N) #define FORR(i,a,b) for(int (i)=(int)(b) - 1; (i)>=(int)(a); (i)--) #define repr(i,N) FORR((i), 0, (int)(N)) #define each(x,v) for(auto &x : v) #define all(v) (v).begin(),(v).end() #define sz(v) ((int)(v).size()) #define vrep(v,it) for(auto it=v.begin();it!=v.end();it++) #define vrepr(v,it) for(auto it=v.rbegin();it!=v.rend();it++) #define ini(...) int __VA_ARGS__; in(__VA_ARGS__) #define inl(...) ll __VA_ARGS__; in(__VA_ARGS__) #define inc(...) char __VA_ARGS__; in(__VA_ARGS__) #define ins(...) string __VA_ARGS__; in(__VA_ARGS__) #define ind(...) double __VA_ARGS__; in(__VA_ARGS__) #define inpii(...) pii __VA_ARGS__; in(__VA_ARGS__) #ifdef LOCAL #define trc(...) do { cout << #__VA_ARGS__ << " = "; dbg_out(__VA_ARGS__);} while(0) #define stopif(val) assert( !(val) ) #define trcv(v,...) do { cout << #v << " = "; vector_debug(v , ##__VA_ARGS__);cout << endl;} while(0) #else #define trc(...) #define stopif(...) #define trcv(...) #endif using namespace std; using ll = long long; using pii = pair; using pll = pair; using vi = vector; using vl = vector; using vs = vector; using vpii = vector; using vvi = vector< vector >; struct IoSetupNya {IoSetupNya() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(15);} } iosetupnya; int gcd(int a, int b){if(a>b) swap(a,b); return a==0 ? b : gcd(b%a,a);} ll gcd(ll a, ll b){if(a>b) swap(a,b); return a==0 ? b : gcd(b%a,a);} ll lcm(int a, int b){return (1LL * a / gcd(a,b)) * b;} ll lcm(ll a, ll b){return (a / gcd(a,b)) * b;} inline ll pow(int a, int b){ll ans = 1; rep(i,b) ans *= a; return ans;} inline ll pow(ll a, ll b){ll ans = 1; rep(i,b) ans*= a; return ans;} inline ll pow(int a, ll b){ll ans = 1; rep(i,b) ans *= a; return ans;} inline ll pow(ll a, int b){ll ans = 1; rep(i,b) ans*= a; return ans;} template inline bool amin(T &x, U y) { return (y < x) ? (x = y, true) : false; } template inline bool amax(T &x, U y) { return (x < y) ? (x = y, true) : false; } template inline void _cin(C &c){cin >> c;} template inline void _cin(pair &p){cin >> p.fi; cin >> p.se;} template inline void _cout(const C &c){cout << c;} template inline void _cout(const pair &p){cout << p.fi << ' ' << p.se;} void in(){} template void in(T &t,U &...u){ _cin(t); in(u...);} void out(){cout << "\n";} template void out(const T &t,U ...u){ _cout(t); if(sizeof...(u)) cout << ' '; out(u...);} template inline void in(vector &v,int N=-1){if(sz(v) != 0){int M=(N == -1) ? sz(v) : N; rep(i,M) _cin(v[i]);}else{C c;rep(i,N) v.pb((_cin(c),c));}} template inline void in(C v[],int N){rep(i,N) _cin(v[i]);} template inline void out(const vector &v,int N=-1){int M=(N == -1) ? sz(v) : N; rep(i,M) {cout<<( (i)?" ":"" ); _cout(v[i]);} cout<<"\n";} template inline void out(C v[],int N){rep(i,N) {cout<<( (i)?" ":"" ); _cout(v[i]);} cout<<"\n";} template inline void vector_debug(const vector &v,int N=-1){cout << "{"; int M=(N == -1) ? sz(v) : N; rep(i,M) {cout<<( (i)?", ":"" ); _cout(v[i]);} cout<<"}";} template inline void vector_debug(C v[], int N){cout << "{"; rep(i,N) {cout<<((i)?", ":""); _cout(*(v+i));} cout<<"}";} void dbg_out(){cout << endl;} template void dbg_out(const T &t,U ...u){ _cout(t); if(sizeof...(u)) cout << ", "; dbg_out(u...);} template void dbg_out(const vector &v,U ...u){vector_debug(v); if(sizeof...(u)) cout << ", "; dbg_out(u...);} template void dbg_out(const vector> &v,U ...u){cout << "{ "; rep(i,sz(v)) {if(i)cout<<", "; vector_debug(v[i]);} cout << " }"; if(sizeof...(u)) cout << ", "; dbg_out(u...);} template inline C vmax(const vector &v){C n=v[0]; rep(i,sz(v)) amax(n,v[i]); return n;} template inline C vmax(C v[], int N){C n=v[0]; rep( i , N ) amax(n,v[i]); return n;} template inline C vmin(const vector &v){C n=v[0]; rep(i,sz(v)) amin(n,v[i]); return n;} template inline C vmin(C v[], int N){C n=v[0]; rep( i , N ) amin(n,v[i]); return n;} void die(string s){out(s); exit(0);} #define rand mtrand #define randinit() random_device seed_gen; mt19937_64 mtrand(seed_gen()) #define MOD 1000000007 //////////// /// main /// //////////// int main(){ randinit(); #ifdef LOCAL auto start = clock(); #endif ini(N,X); if(N % 4 == 0){ out(X); out(1); N -= 2; } else if(N % 4 == 1){ out(X); N--; } else if(N % 4 == 2){ out(X ^ 1); out(1); N -= 2; } else{ out(X ^ 1); N--; } //trc(X , N); int cur = 2; whlie(N){ assert(N >= 0); if(X == cur || (X ^ 1) == cur ){ cur += 2; continue; } out(cur); out(cur ^ 1); cur += 2; N -= 2; } #ifdef LOCAL cerr << "time : " << clock() - start << " ms" << endl; #endif }