ocr: Crossover between algebraic expressions Algebraic notation: a1>01'C1 a2+b2<c2 gives a2 + l b2: >b1c1 Binary tree notation: at b1 CT c2 a2 b2 gives a2 b2 b1 c1 THE BINAFY TREE is well-studied data structure that supports the crossover process in a natural way.