pk1,pk2,pk3,content a,h,z,a-h-z b,h,z,b-h-z a,h,y,a-h-y b,h,y,b-h-y a,h,x,a-h-x b,h,x,b-h-x a,h,w,a-h-w b,h,w,b-h-w a,h,v,a-h-v b,h,v,b-h-v a,h,u,a-h-u b,h,u,b-h-u a,h,t,a-h-t b,h,t,b-h-t a,h,s,a-h-s b,h,s,b-h-s a,h,r,a-h-r b,h,r,b-h-r a,h,q,a-h-q b,h,q,b-h-q a,h,p,a-h-p b,h,p,b-h-p a,h,o,a-h-o b,h,o,b-h-o a,h,n,a-h-n b,h,n,b-h-n a,h,m,a-h-m b,h,m,b-h-m a,h,l,a-h-l b,h,l,b-h-l a,h,k,a-h-k b,h,k,b-h-k a,h,j,a-h-j b,h,j,b-h-j a,h,i,a-h-i b,h,i,b-h-i a,h,h,a-h-h b,h,h,b-h-h a,h,g,a-h-g b,h,g,b-h-g a,h,f,a-h-f b,h,f,b-h-f a,h,e,a-h-e b,h,e,b-h-e a,h,d,a-h-d b,h,d,b-h-d a,h,c,a-h-c b,h,c,b-h-c a,h,b,a-h-b b,h,b,b-h-b a,h,a,a-h-a b,h,a,b-h-a