How to append missing values from a list in sequential order?-CodePudding

Example my 2 list are.

a = [11,22]
b = [33,22,11,44,55]

My expected output should add missing values from b into a in a sequential order.

a = [11,22,33,44,55]

This is my codes to achieve the output

z = (set(b).difference(a))
y = list(z)
for i in y:
    a.append(i)

However if I print(y) it is [33,55,44], why is it not returning [33,44,55]? and how do i achieve my desired output.

CodePudding user response：

It's not adding in sequential order because you are using set and the output can be different every try. You can use list comprehension to achieve this goal.

a = [11,22]
b = [33,22,11,44,55]
a  = [element for element in b if element not in a]

CodePudding user response：

You can use set() method to sort z.
Corrected code :-

a = [11,22] 
b = [33,22,11,44,55]
z = set((set(b).difference(a)))
y = list(z) 
for i in y: 
    a.append(i)
print(a)

CodePudding user response：

a = [11,22]
b = [33,22,11,44,55]

c = list(set(a b))
c.sort()
print(c)

Output:

[11, 22, 33, 44, 55]

CodePudding user response：

a = [11,22]
b = [33,22,11,44,55]
for item in set(b):
   if item not in a:
      a.append(item)
print(a)

Loop through each element of second list(b), add in list(a) if element is not present