Shifting Letters Python Solution with Tests

lcpy gen -n 848   # by problem number
lcpy gen -s shifting_letters   # by problem name

Input: s = "abc", shifts = [3,5,9]
Output: "rpl"
Explanation: We start with "abc".
After shifting the first 1 letters of s by 3, we have "dbc".
After shifting the first 2 letters of s by 5, we have "igc".
After shifting the first 3 letters of s by 9, we have "rpl", the answer.

Input: s = "aaa", shifts = [1,2,3]
Output: "gfd"

class Solution:
    # Time: O(n)
    # Space: O(n)
    def shifting_letters(self, s: str, shifts: list[int]) -> str:
        total = 0
        result = list(s)
        for i in range(len(s) - 1, -1, -1):
            total = (total + shifts[i]) % 26
            result[i] = chr((ord(result[i]) - 97 + total) % 26 + 97)
        return "".join(result)