k,u,v=`dd`.scan(/-?\d+/).map &:to_i;x,y,*s=u.abs,v.abs;d=x+y;x,y=y,x if f=x>y;(k+1)*d%2==1&&(p -1;exit);m=(d-1)/k+1;n=d<k ?2:m+(d-m*k)%2;a=d==k ?x:(d-n*k)/2;b=k-a.abs;d%2-d/k==1&&(s=[[0,-k]];a=b=(d-k)/2);n.times{s<<[a,b];t=[x-a,k].min;a+=t;b+=k-t};p s.size;s.each{|a,b|f&&(a,b=b,a);puts [a*(u<=>0.1),b*(v<=>0.1)]*?\s}