Given a list, the task here is to write a Python program to extract elements which are multiple of all elements of custom list.
Input : test_list = [4, 24, 8, 10, 12, 23], div_list = [6, 4]
Output : [24, 12]
Explanation : 24 and 12 divides 6 and 4 both.Input : test_list = [4, 24, 8, 10, 12, 23], div_list = [6, 4, 7]
Output : []
Explanation : No elements divides 6, 4 and 7.
Method 1: Using list comprehension and all()
In this, we perform task of checking for all elements to be multiple using % operator and all(). List comprehension is used to iterate through all the elements.
Python3
# initializing Listtest_list = [4, 24, 8, 10, 12, 23]# printing original listprint("The original list is : " + str(test_list))# initializing divisor listdiv_list = [6, 4]# using all() to test for all elementsres = [ele for ele in test_list if all(ele % j == 0 for j in div_list)]# printing resultprint("All elements multiple of divisor list : " + str(res)) |
Output:
The original list is : [4, 24, 8, 10, 12, 23]
All elements multiple of divisor list : [24, 12]
Time Complexity: O(n)
Auxiliary Space: O(1)
Method 2: Using filter(), lambda and all()
In this, we perform task of filtering using filter() and lambda, rest all the operations are performed like above method.
Python3
# initializing Listtest_list = [4, 24, 8, 10, 12, 23]# printing original listprint("The original list is : " + str(test_list))# initializing divisor listdiv_list = [6, 4]# using all() to test for all elements# using filter() and lambda to perform filteringres = list(filter(lambda ele: all(ele % j == 0 for j in div_list), test_list))# printing resultprint("All elements multiple of divisor list : " + str(res)) |
Output:
The original list is : [4, 24, 8, 10, 12, 23]
All elements multiple of divisor list : [24, 12]
Time Complexity: O(n), where n is the number of elements in the list “test_list”.
Auxiliary Space: O(n), where n is the number of elements in the list “test_list”.
Method 3: Uses a loop
Step-by-step approach:
- Initialize the input list and the divisor list.
- Initialize an empty list to store the result.
- Loop through each element in the test_list.
- For each element, loop through each divisor in the div_list.
- Check if the current element is divisible by the current divisor. If not, set the flag variable to False and break out of the loop.
- If the flag variable is True after checking all the divisors, append the current element to the result list.
- Print the result.
Python3
# initializing Listtest_list = [4, 24, 8, 10, 12, 23]# printing original listprint("The original list is : " + str(test_list))# initializing divisor listdiv_list = [6, 4]# initializing an empty list to store the resultsres = []# looping through each element in the test_listfor ele in test_list: # initializing a flag variable to keep track of whether the current element is divisible by all the divisors in div_list flag = True # looping through each divisor in div_list for div in div_list: # if the current element is not divisible by any of the divisors in div_list, set the flag to False and break out of the loop if ele % div != 0: flag = False break # if the flag is True, append the current element to the result list if flag: res.append(ele)# printing resultprint("All elements multiple of divisor list : " + str(res)) |
The original list is : [4, 24, 8, 10, 12, 23] All elements multiple of divisor list : [24, 12]
Time complexity: O(n*m), where n is the length of test_list and m is the length of div_list.
Auxiliary space: O(k), where k is the number of elements in the result list.
Method 4: Use the set intersection operation.
Step-by-step approach:
- Convert the div_list to a set using the set() function.
- Create a set comprehension to get a set of all the elements in the test_list that are divisible by all the elements in the div_list set. This can be done using the all() function and the modulus operator (%).
- Convert the resulting set back to a list.
- Print the resulting list.
Python3
# initializing Listtest_list = [4, 24, 8, 10, 12, 23]# printing original listprint("The original list is : " + str(test_list))# initializing divisor listdiv_list = [6, 4]# converting div_list to a setdiv_set = set(div_list)# getting a set of all the elements in the test_list that are divisible by all the elements in the div_list setresult_set = {ele for ele in test_list if all(ele % div == 0 for div in div_set)}# converting the resulting set back to a listres = list(result_set)# printing resultprint("All elements multiple of divisor list : " + str(res)) |
The original list is : [4, 24, 8, 10, 12, 23] All elements multiple of divisor list : [24, 12]
Time complexity: O(n * m), where n is the length of test_list and m is the length of div_list.
Auxiliary space: O(k), where k is the length of the resulting list (res).
