Max Difference You Can Get From Changing An Integer - Leetcode Solution

Problem Statement:

You are given an integer num. You can change at most one digit in num to any other digit to create another integer.

Return the maximum difference between the original number and the resulting number.

Solution:

To solve this problem, we can start by converting the integer into a list of digits. We can then iterate through the digits, trying to change each digit to every possible number between 0 and 9 and calculate the maximum difference.

Here is the step by step approach to solve this problem:

1. Convert num into a list of digits:

digits = [int(d) for d in str(num)]

2. Iterate through the digits and try to change each digit to every possible number between 0 and 9:

max_diff = 0
for i in range(len(digits)):
    for j in range(10):
        # Change the digit i to j
        new_digits = digits[:]
        new_digits[i] = j
        
        # Calculate the difference between the new number and the original number
        new_num = int(''.join(map(str, new_digits)))
        diff = new_num - num
        max_diff = max(max_diff, diff)

3. Return the maximum difference:

return max_diff

Here is the complete code:

class Solution:
    def maxDiff(self, num: int) -> int:
        digits = [int(d) for d in str(num)]
        max_diff = 0
        for i in range(len(digits)):
            for j in range(10):
                # Change the digit i to j
                new_digits = digits[:]
                new_digits[i] = j
                
                # Calculate the difference between the new number and the original number
                new_num = int(''.join(map(str, new_digits)))
                diff = new_num - num
                max_diff = max(max_diff, diff)
        
        return max_diff

Time Complexity: O(N) where N is the number of digits in num.

Space Complexity: O(N) where N is the number of digits in num.

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