如何检查列表中是否只有一个 position 为空白，其他所有不是

Question

I have a list

list = [' ' for x in range(10)]

If I add values to this list, how do I check that only list[0] is blank and list[1] - list[9] are not?

Answer 1

Assuming l is the list containing the values, you can do something like:

if l[0] == ' ' and all(s != ' ' for s in l[1:9]):
    print("Complete!!!!!!")

Answer 2

You can use all

list1=[' ' if i==0 else i for i in range(10) ]
if list1[0]==" " and all(x!=' ' for x in list1[1:9]):
    print("Complete List!!!")

Answer 3

The easiest, most straight forward way is to just write a loop to go through each element. Keep track of what the element is and then do something with that information.

A way for you to know that would constant time would be to track how many different indices you have changed, and then to just check how many empty spaces there are left.