Given two lists and check list, test if for each element in check list, elements occur in similar index in 2 lists.
Input : test_list1 = [2, 6, 9, 7, 8], test_list2 = [2, 7, 9, 4, 8], check_list = [9, 8, 7] Output : False Explanation : 7 is at 4th and 2nd place in both list, hence False. Input : test_list1 = [2, 6, 9, 7, 8], test_list2 = [2, 6, 9, 4, 8], check_list = [9, 8, 6] Output : True Explanation : All from checklist at similar index, hence True.
Method #1 : Using loop
In this, we iterate for all the elements in list, if elements are different and is present in check list, then False is returned.
Python3
# Python3 code to demonstrate working of # Check if elements index are equal for list elements# Using loop# initializing liststest_list1 = [2, 6, 9, 7, 8]test_list2 = [2, 7, 9, 4, 8]# printing original listsprint("The original list 1 : " + str(test_list1))print("The original list 2 : " + str(test_list2))# initializing check_listcheck_list = [9, 8, 2]res = Truefor idx, ele in enumerate(test_list1): # check for indifference and containment if test_list1[idx] != test_list2[idx] and ele in check_list: res = False break # printing result print("Are elements at same index for required instances ?: " + str(res)) |
The original list 1 : [2, 6, 9, 7, 8] The original list 2 : [2, 7, 9, 4, 8] Are elements at same index for required instances ?: True
Time Complexity: O(n), where n is the length of the input list.
Auxiliary Space: O(n) additional space of size n is created where n is the number of elements in the list “test_list”.
Method #2 : Using zip() + all() + generator expression
In this, we pair like indices using zip() and then all() is used to check for all indices, generator expression is used for iteration logic.
Python3
# Python3 code to demonstrate working of # Check if elements index are equal for list elements# Using zip() + all() + generator expression# initializing liststest_list1 = [2, 6, 9, 7, 8]test_list2 = [2, 7, 9, 4, 8]# printing original listsprint("The original list 1 : " + str(test_list1))print("The original list 2 : " + str(test_list2))# initializing check_listcheck_list = [9, 8, 2]# checking for all elements equal in check list using all()res = all(a == b for a, b in zip(test_list1, test_list2) if a in check_list) # printing result print("Are elements at same index for required instances ?: " + str(res)) |
The original list 1 : [2, 6, 9, 7, 8] The original list 2 : [2, 7, 9, 4, 8] Are elements at same index for required instances ?: True
Method#3:Using list comprehension
Python3
# initializing liststest_list1 = [2, 6, 9, 7, 8]test_list2 = [2, 7, 9, 4, 8]# printing original listsprint("The original list 1 : " + str(test_list1))print("The original list 2 : " + str(test_list2))# initializing check_listcheck_list = [9, 8, 2]# Using a list comprehension and the all function# all returns True if all elements in the iterable are True, otherwise Falseres = all(test_list1[i] == test_list2[i] for i in range(len(test_list1)) if test_list1[i] in check_list)# printing result print("Are elements at same index for required instances ?: " + str(res))#This code is contributed by Vinay Pinjala. |
The original list 1 : [2, 6, 9, 7, 8] The original list 2 : [2, 7, 9, 4, 8] Are elements at same index for required instances ?: True
Time Complexity: O(n)
Auxiliary Space: O(n)
