Python: agregar elementos faltantes de otra lista

Dadas 2 listas, agregue los elementos que faltan de la lista 1 a la lista 2.

Entrada : test_list1 = [5, 6, 4, 8, 9, 1], test_list2 = [9, 8, 10]
Salida : [5, 6, 4, 1, 9, 8, 10]
Explicación : 5, 6, 4, 1 agregado a la lista 2, en orden.

Entrada : test_list1 = [5, 6, 4, 8, 9, 1], test_list2 = [9, 10]
Salida : [5, 6, 4, 8, 1, 9, 10]
Explicación : 5, 6, 4, 8, 1 agregado a la lista 2, en orden.

Método #1: Usar la comprensión de listas

En esto, iteramos la lista 1 para verificar los elementos faltantes en la lista 2, luego agregamos estos elementos a la lista 2.

# Python3 code to demonstrate working of 
# Append Missing elements from other List
# Using list comprehension
  
# initializing list
test_list1 = [5, 6, 4, 8, 9, 1]
test_list2 = [9, 8, 7]
  
# printing original lists
print("The original list 1 is : " + str(test_list1))
print("The original list 2 is : " + str(test_list2))
  
# extracting elements from list 1 which are not in list 2
temp1 = [ele for ele in test_list1 if ele not in test_list2]
  
# constructing result 
res = temp1 + test_list2
  
# printing result 
print("The modified list 2 : " + str(res))

The original list 1 is : [5, 6, 4, 8, 9, 1]
The original list 2 is : [9, 8, 7]
The modified list 2 : [5, 6, 4, 1, 9, 8, 7]

Método #2: Usar set() + operador “-” + extender()

En esto, verificamos los elementos de la lista 1 que faltan en la lista 2 usando el operador set() y – y extend() se usa para unir la lista y obtener el resultado deseado.

# Python3 code to demonstrate working of 
# Append Missing elements from other List
# Using set() + "-" operator + extend()
  
# initializing list
test_list1 = [5, 6, 4, 8, 9, 1]
test_list2 = [9, 8, 7]
  
# printing original lists
print("The original list 1 is : " + str(test_list1))
print("The original list 2 is : " + str(test_list2))
  
# finding missing words
rem_list = (set(test_list1) - set(test_list2))
  
# checking order
res = [ele for ele in test_list1 if ele in rem_list] 
  
# joining result
res.extend(test_list2)
  
# printing result 
print("The modified list 2 : " + str(res))

The original list 1 is : [5, 6, 4, 8, 9, 1]
The original list 2 is : [9, 8, 7]
The modified list 2 : [5, 6, 4, 1, 9, 8, 7]