Python | Maximum Difference in String

Sometimes, we might have a problem in which we require to get the maximum difference of 2 numbers from Strings but with a constraint of having the numbers in successions. This type of problem can occur while competitive programming. Let’s discuss certain ways in which this problem can be solved.

 Method #1 : Using max() + zip() + list comprehension This problem can be solved using the combination of above three function in which max function can be used to get the max value, zip and list comprehension doing the task of extending the logic to the whole list. 

The original string : 6543452345456987653234
The maximum consecutive difference is : 3

Time Complexity: O(N), Where N is the length of the given string
Auxiliary Space: O(N)

Method #2 : Using max() + map() + operator.sub The above problem can also be solved using yet another combination of functions. In this combination, map functions performs the task of extending the logic to whole list and sub operator is used to perform the difference. 

The original string : 6543452345456987653234
The maximum consecutive difference is : 3

Time Complexity: O(N), Where N is the length of the given string
Auxiliary Space: O(N)

Method #3 : Using max() + enumerate() + list comprehension
This problem can also be solved using the combination of max function, enumerate function and list comprehension. Enumerate function helps to generate the index of each element in the list and max helps to get the maximum value of the consecutive difference. 
 

The original string : 6543452345456987653234
The maximum consecutive difference is : 3

Time Complexity: O(N), Where N is the length of the given string
Auxiliary Space: O(N)

Method #4: Using itertools pairwise and max()

We can also use the pairwise() function from the itertools module to generate pairs of adjacent characters in the string. Then we can use max() to find the maximum difference between adjacent pairs.

Here are the steps:

Import the itertools module.
Define the test_string.
Generate pairs of adjacent characters using pairwise() function.
Calculate the absolute difference between the pairs using a list comprehension.
Find the maximum difference using max() function.
Print the result.

OUTPUT : 
The original string : 6543452345456987653234
The maximum consecutive difference is : 3

Time complexity: O(n)
Auxiliary space: O(n)