#include using namespace std; typedef signed long long ll; #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define FORR2(x,y,arr) for(auto& [x,y]:arr) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) template bool chmax(T &a, const T &b) { if(a bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;} //------------------------------------------------------- ll N,K; void solve() { int i,j,k,l,r,x,y; string s; cin>>N>>K; ll mi=N-1; ll ma=0; if(N%2==0) { ma=(N/2+1+N)*(N/2)-(N/2+1); ma-=(1+N/2)*(N/2)-N/2; } else { ma=(N/2+2+N)*(N/2)-(N/2+2)+N/2+1; ma-=(1+N/2)*(N/2); } if(K>=mi&&K<=N*(N-1)/2) { vector A,B,C,D; for(int L=1,R=N;L<=R;) { C.push_back(L++); if(L<=R) C.push_back(R--); } FORR(c,C) { if(A.empty()) { A.push_back(c); } else { if(abs(c-A.back())<=K) { K-=abs(c-A.back()); A.push_back(c); } else { D.push_back(c); } } } cout<=mi&&K<=ma) { vector R; if(N%2==0) { FOR(i,N/2) { R.push_back(N/2+1+i); R.push_back(1+i); } } else { FOR(i,N/2) { R.push_back(N/2+2+i); R.push_back(1+i); } R.push_back(N/2+1); } ll dif=ma-K; assert(dif<=N/2); if(dif) swap(R[(dif-1)*2],R[N-1]); FORR(r,R) cout<