class Nod:
    def __init__(self, e):
        self.e = e
        self.urm = None


class Lista:
    def __init__(self):
        self.prim = None


'''
crearea unei liste din valori citite pana la 0
'''


def creareLista():
    lista = Lista()
    lista.prim = creareLista_rec()
    return lista


def creareLista_rec():
    x = int(input("x="))
    if x == 0:
        return None
    else:
        nod = Nod(x)
        nod.urm = creareLista_rec()
        return nod


'''
tiparirea elementelor unei liste
'''

'''
def tipar(lista):
    tipar_rec(lista.prim)


def tipar_rec(nod):
    if nod != None:
        print(nod.e)
        tipar_rec(nod.urm)
'''

'''
program pentru test
'''



def number(list):
    if list == []:
        return 0
    elif list[0] % 2 == 0:
        return list[0] + number(list[1:])
    elif list[0] % 2 != 0:
        return -list[0] + number(list[1:])

newList = []


def difference(list1, list2):

    if list1 == [] and newList == []:
        return list2
    elif list2 == [] and newList == []:
        return list1
    elif list1 == [] :
        #return list2
        return newList
    elif list2 == []:
        #return list1
        return newList
    elif list1[0] == list2[0]:
        return difference(list1[1:], list2[1:])
    elif list1[0] > list2[0]:
        newList.insert(0, list2[0])
        return difference(list1, list2[1:])
    elif list1[0] < list2[0]:
        newList.insert(0, list1[0])
        return difference(list1[1:], list2)


def main():
    #list = creareLista()
    listtttttt = []
    list = [1, 2, 3, 4, 5, 6]

    print(number(list))

    list1 = [1, 2, 3, 4, 5, 6]
    list2 = [1, 3, 6]
    #list2 = []
    print(difference(list1, list2))

    #tipar(list)


main()