字母移位

// Solution using Java Stream
// Here we use Streams to accumulate the total shifts and apply them to each character.
// We reverse the shifts array to make the calculation easier, then convert it back.

import java.util.stream.IntStream;

public class Solution {
    public String shiftingLetters(String s, int[] shifts) {
        char[] chars = s.toCharArray();
        int n = s.length();
        long[] totalShifts = new long[n];
        totalShifts[n - 1] = shifts[n - 1];
        // Calculate total shifts for each character starting from the end
        IntStream.range(0, n - 1)
            .mapToObj(i -> n - 2 - i)
            .forEach(i -> totalShifts[i] = (totalShifts[i + 1] + shifts[i]) % 26);
        // Apply the shifts to each character
        IntStream.range(0, n).forEach(i ->
            chars[i] = (char) ((chars[i] - 'a' + totalShifts[i]) % 26 + 'a')
        );
        return new String(chars);
    }
}