How can I merge multiple unknown number of lists together?-CodePudding

Based on the number of time the for loop runs, I get multiple list. I want to merge all those list and make one list.

for example:

list = []

for i in item:
   list.append(i)
print(list)

How can I merge all the list I get to one list ?

CodePudding user response：

If your item is list of lists, then you can use extend to achieve the same.

lst = []
    
for i in item:
   lst.append(i)

out = []
for sublist in lst:
    out.extend(sublist)

print(out)

Also, avoid using python keywords like list for the variable name, use something like lst instead.

CodePudding user response：


list1 = ["hey"]

list2 = ["yo"]

list1.append(list2) = ["hey", ["yo"]]
list1.extend(list2) = ["hey", "yo"]
list1 = list   list2 = ["hey", "yo"]

CodePudding user response：

You should avoid using list as a variable name, it's a reserved word for python lists.

This code should work for you:

list_ = []
f_list = []

item = [1,2,3,4,5]

for i in item:
    list_.append(i)
    f_list.extend(list_)
    print(list_)
print("Final list - ", f_list)

Output:

[1]
[1, 2]
[1, 2, 3]
[1, 2, 3, 4]
[1, 2, 3, 4, 5]
Final list -  [1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1, 2, 3, 4, 5]