repli set object reach receiv set take step defin given child gener result includ element origin set order avoid deep search program mistak path given max length consid path consist element caus predic evalu consid param cg given childgener param max maximum depth param predic predic object fulfil result listset list set transit closur argouml util child gener cg max argouml util predic predic iter count size list set touch list set list set frontier list set recent touch add iter count max touch size size iter count size touch size frontier list set recent recent element recent iter frontier children cg child iter recent element frontier add element frontier children predic touch add frontier recent frontier touch 