[99{(%stdin)(r)file 20 string readline{[exch(:)search[5 4 roll cvx exec]]0}if
pop}repeat]dup length{dup{aload pop{1 sub 4 index exch get 2 get not
and}forall{dup = cvi 1 sub 2 index exch get 2 false put exit}if def}forall
pop}repeat