Algo_IT(T,P,x)

ST=STA=STP=LAST=NIL
CT=T ; CP = P;
while(CT != NIL || ST != NIL) do
	if(CT != NIL) then
		ret = 0
		ST = push(ST,CT)
		STP = push(STP, CP)
		CT = CT->SX
		P = CT
	else //risalgo dalla prima chiamata ricorsiva riga 3
		CT = TOP (ST) ; CP = TOP(STP) ;
		if ( LAST =! CT->DX && CT->DX != NIL ) then
			a = val;
			STA = push(STA, A)
			CT=CT->DX
			P=CT
		else
			if (LAST = CT->DX) then
				b=val
				TOP(STA); POP(STA);
				ret = a+b+1
			else
				a=val
				b=0
				ret=a+b+1
			if(CT->Key%2 = 0 ^ ret < x ^ P != NIL) then
				if(CT=CP->DX)then
					CP->DX=cancella_radice(CT)
				else
					CP->SX=cancella_radice(CT)
			Pop(ST);Pop(STP);
			LAST = CT;
			CT = NIL;
			return ret;