n,*k=$<.read.split.map &:to_i
w=->a,f{(0..a.size-1).to_a.combination(3).send(f>0?:select: :any?){|r|i,j,k=r;a[i]!=a[k]&&(a[i]<=>a[j])*(a[j]<=>a[k])<0&&(b=a.dup;[k,j,i].map{|e|b.delete_at(e)};!w[b,0])}}
puts w[k,1].map{|r|r*" "}[0]||-1