[ASD] RIC-IT 16/10/2017

ALGO_IT(T, a, b)
	curr=T, last=nextT= NIL,
	currA=a, currB=b, nextA= nextB= -1
	S_T=S_b= NIL

	while(curr != NIL || S_T != NIL) do
		if (curr != NIL) then    //NUOVA CHIAMATA
			if( curr->key >= currA && curr->key <= currB) then
				push(S_T, curr)
				push(S_b, currB)
				next= curr->sx    //DISCESA A SX
				nextA= currA
				nextB= curr->key
			else
				CANCELLA_TREE(curr)
				ret= NIL    //ISTRUZIONI CHE SIMULANO return T
				next= NIL

		else
			curr= top(S_T)
			currB= top(S_b)
			if (last != curr->dx && curr->dx != NIL) then //STO TORNANDO DA SX
				curr->sx= ret
				next= curr->dx //PREPARO DISCESA A DX
				nextA= curr->key
				nextB= currB
			else
				pop(S_T)
				pop(S_b)
				if (curr->dx != NIL) then //STO TORNANDO DA DX
					curr->dx= ret
				else //SONO TORNATO DA SX MA IL DX E' NIL
					curr->dx= NIL
				ret= curr
				next= NIL

		last=curr
		curr=next
		currA= nextA
		currB= nextB

	return curr