etudiant(et001,ibolya,bagyi)->;
etudiant(et002,yue,zhoyu)->;
etudinat(et003,marie,jeanraut)->;
etudinat(et004,ivan,fontarensky)->;
etudinat(et005,ailing,jeam)->;
etudinat(et006,amadu,jeam)->;

binomes(bi1,et001,et002)->;
binomes(bi2,et003,et004)->;
binomes(bi3,et005,et006)->;

inscrit(et001,compi)->;
inscrit(et002,compi)->;
inscrit(et003,compi)->;
inscrit(et004,compi)->;
inscrit(et005,compi)->;
inscrit(et006,compi)->;
inscrit(et001,fonctionnelle)->;
inscrit(et002,fonctionnelle)->;
inscrit(et003,fonctionnelle)->;
inscrit(et004,fonctionnelle)->;
inscrit(et005,systeme)->;
inscrit(et006,systeme)->;

notes(et001,compi,12)->;
notes(et001,compi,20)->;
notes(et002,compi,14)->;
notes(et003,compi,15)->;
notes(et004,compi,12)->;
notes(et005,compi,16)->;
notes(et006,compi,17)->;
notes(et001,fonctionnelle,10)->;
notes(et002,fonctionnelle,12)->;
notes(et003,fonctionnelle,13)->;
notes(et004,fonctionnelle,14)->;
notes(et005,systeme,15)->;
notes(et006,systeme,16)->;



/*preparer(x,y)->rule(notes(x,y,z),nil)
		assert(noteutile(x,y,z),nil)
		fail; */
preparer(x,y)-> notes(x,y,z)
		asserta(noteutile(x,y,z),nil)
		fail;
preparer(x,y)->;


somme(x,y,s,n)-> retract (noteutile(x,y,z),nil) 
                 !
		 somme(x,y,s1,n1)
		 val(add(s1,z),s)
		 val(add(n1,1),n);
somme(x,y,0,0)->;


calculer(x,y,m)->somme(x,y,s,n)
		val(div(s,n),m);


effacer->retract(noteutile(x,y,z),nil)
		fail;
effacer->;

moyenne(x,y,m)->effacer
		preparer(x,y)
	   	calculer(x,y,m);