Python | Combine two lists by maintaining duplicates in first list
Given two lists, the task is to combine two lists and removing duplicates, without removing duplicates in original list.
Example:
Input : list_1 = [11, 22, 22, 15] list_2 = [22, 15, 77, 9] Output : OutList = [11, 22, 22, 15, 77, 9]
Code #1: using extend
# Python code to combine two lists # and removing duplicates, without # removing duplicates in original list. # Initialisation of first list list1 = [ 111 , 222 , 222 , 115 ] # Initialisation of Second list list2 = [ 222 , 115 , 77 , 19 ] output = list (list1) # Using extend function output.extend(y for y in list2 if y not in output) # printing result print (output) |
Output:
[111, 222, 222, 115, 77, 19]
Code #2 : Using Set and Iteration
Append those element in first list which are not in second list and then take union of first and second list.
# Python code to combine two lists # and removing duplicates, without # removing duplicates in original list. # Initialisation of first list list1 = [ 11 , 22 , 22 , 15 ] # Initialisation of Second list list2 = [ 22 , 15 , 77 , 9 ] # creating set unique_list1 = set (list1) unique_list2 = set (list2) # Difference in two sets diff_element = unique_list2 - unique_list1 # union of difference + first list output = list1 + list (diff_element) # printing output print (output) |
Output:
[11, 22, 22, 15, 9, 77]