Lists

Question

myUniqueList = []

def add(x):
myUniqueList.append(x)

add(10)
print(myUniqueList)

Can anyone helo me create the code i dont understand English that good and the code above is how far i got and i dont know how to write the rest that it asks (i am learning the python from an website and the gave me this homework)

Create a global variable called myUniqueList. It should be an empty list to start.

Next, create a function that allows you to add things to that list. Anything that's passed to this function should get added to myUniqueList, unless its value already exists in myUniqueList. If the value doesn't exist already, it should be added and the function should return True. If the value does exist, it should not be added, and the function should return False;

Finally, add some code below your function that tests it out. It should add a few different elements, showcasing the different scenarios, and then finally it should print the value of myUniqueList to show that it worked.

Answer 1

Okay, you're off to a good start. However, a couple of things need to be added. Because myUniqueList is a global list, if we want to use it in a function we need to inform the function we're using it by doing this:
global myUniqueList
You can place this inside your function. Next, we also need to check if the parameter provided to the function is already in myUniqueList. We can do this by using in:
if x in myUniqueList: #if x is already in myUniqueList
return False #the challenge asks you to return False if x is already in myUniqueList
else:
myUniqueList.append(x) #if it's not, we can append it
return True #and return True, which the challenge tells us to do
Try this out, and add a couple of examples to see if it works.

Answer 2

All it says is that if you have entered 10 once in the list then if you try to add the same value again to the list then it should not be allowed. You just have to avoid duplicates, be it any type you are passing in the method.

Answer 3

Ok ty

Answer 4

myUniqueList = []
def add(x):
if x in myUniqueList:
return False
else:
myUniqueList.append(x)
return True

add(9)
print(myUniqueList)

How do i make it so it remembers whats already in list

Answer 5

You need to use the global variable, after defining add():
def add(x):
global myUniqueList
#rest of your code goes here

Answer 6

Def add(×):
Global myUniqueList = []

Or i just add the variable above the func and do it like you said:

MyUniqueList = []
Def add(x):
Global myUniqueList
...
Like this ?

Answer 7

The bottom one is correct(global and def should be all lowercase though).

Answer 8

Ok ty

Answer 9

myUniqueList = []
def add(x):
global myUniqueList
if x in myUniqueList:
return False
else:
myUniqueList.append(x)
return True

add(10)
print(myUniqueList)

But how is the if x in myUniquelist part is supposed to work it doesnt return me false if i keep on hitting run with the same number

Answer 10

It works. If you want to see whether the function returns True or False, you would have to use a print() statement, like this:
print(add(10))
Or:
ten = add(10) #basically, a value is given to the function, which is exchanged to the variable
print(ten)
So, if you were to run this:
print(add(10))
print(add(20))
print(add(10))
print(myUniqueList)
The result in the console would be:
True
True
False
[10, 20]

Answer 11

I tryed to run it it all works but when i keep adding the same number ir returns me the same number and true and when i run it with different number they dont stack up in the list it just shows a different number and true

myUniqueList = []

def add(x):
global myUniqueList
if x in myUniqueList
return False
else:
myUniqueList.append(x)
return true

print(add(10))

print (myUniqueList)

#running the code two times
output:
True
[10]
True
[10]

Answer 12

It works fine for me.

Answer 13

@kasisX actually in your code there is indentation mistake in else section and you cannot use colon : after if, you write true in the small letter but it is the not right way writing true, in boolean you write true like this:- True and you do not call add function twice with the same value for checking, when you call add function twice with same value then it gives first time True and other time False.

Try this code I solved all your mistake in this code:-

myUniqueList = []

def add(x):
global myUniqueList
if x in myUniqueList:
return False

else:
myUniqueList.append(x)
return True

print(add(10))

print (myUniqueList)

print(add(10))
print(myUniqueList)

#running the code two times
#output:
# True
# [10]
# True
# [10]

Answer 14

Man this was 2 months ago but thanks anyways now i understand i had to do double print for func and list ty

Answer 15

Add another function that pushes all the rejected inputs into a separate global array called myLeftovers. If someone tries to add a value to myUniqueList but it's rejected (for non-uniqueness), it should get added to myLeftovers instead.?/??