Sum of Digits of String After Convert

First convert the string s into a new string that represents the positions of the letters in the alphabet. Then, convert this new string into an integer, and repeatedly replace this integer with the sum of its digits k times. Return the final integer.

Here is the Python code:

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class Solution:
    def getLucky(self, s: str, k: int) -> int:
        # Create a list to store the positions of the letters in the alphabet.
        positions = []

        # For each letter in s, get its position in the alphabet and append it to the list.
        for letter in s:
            position = ord(letter) - ord('a') + 1
            positions.append(str(position))

        # Convert the list into a string, and then into an integer.
        num = int(''.join(positions))

        # Repeat the transform operation k times.
        for _ in range(k):
            num = sum(int(digit) for digit in str(num))

        return num

This code starts by creating an empty list positions to store the positions of the letters in the alphabet. It then goes through each letter in s, calculates its position in the alphabet (with ‘a’ being 1, ‘b’ being 2, etc.), and appends this position to positions. After that, it joins positions into a string and converts this string into an integer num.

Next, it performs the transform operation k times. In each iteration, it converts num into a string, goes through each digit in this string, converts it back into an integer, and adds all these integers together. The result is the new value of num. Finally, it returns num.