Digit-String Half Anagram

Frequency: Reported

Given a string containing only digits, modify its first half so that it becomes an anagram of the second half. In one operation, replace any digit with any other digit from 0 through 9. Return the minimum number of operations.

Example

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s = "123212"

The halves are "123" and "212". Replace the 3 in the first half with 2, producing "122", which is an anagram of the second half. Return 1.

Function

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getAnagram(string s) -> int

Constraints

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1 < n < 10^5
s contains digits only
len(s) is a multiple of 2

Submitted implementation

python

def getAnagram(s):
    n = len(s)
    half = n // 2
    first_half = s[:half]
    second_half = s[half:]

    count_first = [0] * 10
    count_second = [0] * 10

    for digit in first_half:
        count_first[int(digit)] += 1

    for digit in second_half:
        count_second[int(digit)] += 1

    operations = 0
    for i in range(10):
        if count_first[i] > count_second[i]:
            operations += count_first[i] - count_second[i]

    return operations