nullMarked_cdr.Marked_revcdrMarked_++revtrueMarked_null++Marked_carcarfalsenilzyxrev(nil)nilrev(.(x,y))++(rev(y),.(x,nil))car(.(x,y))xcdr(.(x,y))ynull(nil)truenull(.(x,y))false++(nil,y)y++(.(x,y),z).(x,++(y,z))rev(nil)nilrev(.(x,y))++(rev(y),.(x,nil))car(.(x,y))xcdr(.(x,y))ynull(nil)truenull(.(x,y))false++(nil,y)y++(.(x,y),z).(x,++(y,z))Marked_rev(.(x,y))Marked_++(rev(y),.(x,nil))Marked_rev(.(x,y))Marked_rev(y)Marked_++(.(x,y),z)Marked_++(y,z)rev(nil)nilrev(.(x,y))++(rev(y),.(x,nil))car(.(x,y))xcdr(.(x,y))ynull(nil)truenull(.(x,y))false++(nil,y)y++(.(x,y),z).(x,++(y,z))Marked_rev(.(x,y))Marked_rev(y)nil0false0car330++120true30rev20cdr330Marked_rev30.2210null330rev(nil)nilrev(.(x,y))++(rev(y),.(x,nil))car(.(x,y))xcdr(.(x,y))ynull(nil)truenull(.(x,y))false++(nil,y)y++(.(x,y),z).(x,++(y,z))Marked_++(.(x,y),z)Marked_++(y,z)nil0false30car230++120true30rev20Marked_++30cdr230.1110null330