class LogicGate:

    def __init__(self,n):
        self.label = n
        self.output = None

    def getLabel(self):
        return self.label

    def getOutput(self):
        self.output = self.performGateLogic()
        return self.output

class BinaryGate(LogicGate):

    def __init__(self,n):
        LogicGate.__init__(self,n)

        self.pinA = None
        self.pinB = None

    def getPinA(self):
        if self.pinA == None:
            return input("Enter Pin A input for gate "+ \
                                self.getLabel()+"-->")
        else:
            return self.pinA.getFrom().getOutput()

    def getPinB(self):
        if self.pinB == None:
            return input("Enter Pin B input for gate "+ \
                                self.getLabel()+"-->")
        else:
            return self.pinB.getFrom().getOutput()

    def setNextPin(self,source):
	     if self.pinA == None:
	         self.pinA = source
	     else:
            if self.pinB == None:
		          self.pinB = source
	         else:
		          print "Cannot Connect: NO EMPTY PINS"

class AndGate(BinaryGate):

    def __init__(self,n):
        BinaryGate.__init__(self,n)

    def performGateLogic(self):

        a = self.getPinA()
        b = self.getPinB()
        if a==1 and b==1:
            return 1
        else:
            return 0

class OrGate(BinaryGate):

    def __init__(self,n):
        BinaryGate.__init__(self,n)

    def performGateLogic(self):
        a = self.getPinA()
        b = self.getPinB()
        if a ==1 or b==1:
            return 1
        else:
            return 0

class UnaryGate(LogicGate):

    def __init__(self,n):
        LogicGate.__init__(self,n)

        self.pin = None

    def getPin(self):
        if self.pin == None:
            return input("Enter Pin input for gate "+ \
                                self.getLabel()+"-->")
        else:
            return self.pin.getFrom().getOutput()

    def setNextPin(self,source):
        if self.pin == None:
	         self.pin = source
	     else:
	         print "Cannot Connect: NO EMPTY PINS"

class NotGate(UnaryGate):

    def __init__(self,n):
        UnaryGate.__init__(self,n)

    def performGateLogic(self):

        if self.getPin():
	         return 0
	     else:
	         return 1

class Connector:

    def __init__(self, fgate, tgate):
        self.fromgate = fgate
        self.togate = tgate

        tgate.setNextPin(self)

    def getFrom(self):
        return self.fromgate

    def getTo(self):
        return self.togate