Given two lists, the task is to write a Python program to find maximum difference among like index elements.
Examples:
Input : test_list1 = [3, 4, 2, 1, 7], test_list2 = [6, 2, 1, 9, 1]
Output : 8
Explanation : 9 – 1 = 8 is maximum difference across lists in same index.Input : test_list1 = [3, 4, 2, 1, 17], test_list2 = [6, 2, 1, 9, 1]
Output : 16
Explanation : 17 – 1 = 16 is maximum difference across lists in same index.
Method 1 : Using list comprehension + max()
In this, difference is computed using abs() and iteration is done using list comprehension. The max() is used for the task of getting maximum difference among computed sub result.
Python3
# Python3 code to demonstrate working of# Maximum difference across lists# Using list comprehension + max()# initializing liststest_list1 = [3, 4, 2, 1, 7]test_list2 = [6, 2, 1, 9, 1]# printing original listsprint("The original list 1 is : " + str(test_list1))print("The original list 2 is : " + str(test_list2))# using max() to get maximum of extracted differenceres = max(abs(test_list2[idx] - test_list1[idx]) for idx in range(len(test_list1)))# printing resultprint("Maximum difference among lists : " + str(res)) |
The original list 1 is : [3, 4, 2, 1, 7] The original list 2 is : [6, 2, 1, 9, 1] Maximum difference among lists : 8
Time Complexity: O(n)
Auxiliary Space: O(n)
Method 2 : Using zip() + max()
In this pairing of like index elements is done using zip(). Rest all the functionality is similar to above method.
Python3
# Python3 code to demonstrate working of# Maximum difference across lists# Using zip() + max()# initializing liststest_list1 = [3, 4, 2, 1, 7]test_list2 = [6, 2, 1, 9, 1]# printing original listsprint("The original list 1 is : " + str(test_list1))print("The original list 2 is : " + str(test_list2))# using max() to get maximum of extracted difference# zip() used to bind elementsres = max(abs(ele1 - ele2) for ele1, ele2 in zip(test_list1, test_list2))# printing resultprint("Maximum difference among lists : " + str(res)) |
Output:
The original list 1 is : [3, 4, 2, 1, 7] The original list 2 is : [6, 2, 1, 9, 1] Maximum difference among lists : 8
Time Complexity: O(n) where n is the number of elements in the list “test_list”. The zip() + max() is used to perform the task and it takes O(n) time.
Auxiliary Space: O(n) additional space of size O(n) is required
Method #3: Using abs(), for loop
Approach:
- First we need to check if both lists have the same length or not.
- If not, then return “Lists have different lengths”.
- Then iterate through both lists at the same time using a for loop and calculate the absolute difference between each corresponding element of both lists.
- Keep track of the maximum difference found so far using a variable.
- Return the maximum difference found.
Python3
# fn to return the max difference at same position in listsdef max_diff_lists(list1, list2): if len(list1) != len(list2): return "Lists have different lengths" max_diff = 0 for i in range(len(list1)): diff = abs(list1[i] - list2[i]) if diff > max_diff: max_diff = diff return max_diff# Example usagetest_list1 = [3, 4, 2, 1, 7]test_list2 = [6, 2, 1, 9, 1]# Printing Inputsprint("The original list 1: ", test_list1)print("The original list 2: ", test_list2)# Calling fn, printing resultprint("Maximum difference among lists is: ", max_diff_lists(test_list1, test_list2))# This code is developed by mohan balaji battu |
The original list 1: [3, 4, 2, 1, 7] The original list 2: [6, 2, 1, 9, 1] Maximum difference among lists is: 8
Time Complexity: O(n)
Auxiliary Space: O(1)
