#include //ios::sync_with_stdio(false);cin.tie(0);cout.tie(0); using namespace std; typedef long long ll; typedef unsigned long long ull; typedef pair pii; typedef pair ppii; typedef pair pipi; typedef pair pll; typedef pair ppll; typedef pair plpl; typedef tuple tl; ll mod=1000000007; ll mod2=998244353; ll mod3=1000003; ll mod4=998244853; ll inf=1000000000; double pi=2*acos(0); #define rep(i,m,n) for(ll i=m;i=m;i--) 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}; ll lmax(ll a,ll b){ if(a0){ if(k&1)ret*=now; now*=now; k/=2; } return ret; } int main(){ ios::sync_with_stdio(false);cin.tie(0); int n,k;cin>>n>>k; if(n==1&&k==1){ cout<<"Yes"< v[k]; rep(i,0,n/k){ rep(j,i*k,(i+1)*k){ if(i%2==0)v[j%k].push_back(j+1); else v[k-1-j%k].push_back(j+1); } } rep(i,0,k){ rep(j,0,v[i].size())cout< v[k+1]; rep(i,1,k+1)v[i].push_back(i); int kk=k/2+1; rep(i,kk,k+1){ v[i].push_back(i-kk+1+k); } rep(i,1,kk)v[i].push_back(i+kk+k); int nr=k,nl=kk-1; rep(i,2*k+1,3*k+1){ if(i%2==0){ v[nl].push_back(i); nl--; } else{ v[nr].push_back(i); nr--; } } rep(i,3,n/k){ rep(j,i*k,(i+1)*k){ if(i%2==1)v[j%k+1].push_back(j+1); else v[k-j%k].push_back(j+1); } } rep(i,1,k+1){ rep(j,0,v[i].size())cout<