#2381

Shifting Letters II

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Description

You are given a string s of lowercase English letters and a 2D integer array shifts where shifts[i] = [starti, endi, directioni]. For every i, shift the characters in s from the index starti to the index endi (inclusive) forward if directioni = 1, or shift the characters backward if directioni = 0.

Shifting a character forward means replacing it with the next letter in the alphabet (wrapping around so that 'z' becomes 'a'). Similarly, shifting a character backward means replacing it with the previous letter in the alphabet (wrapping around so that 'a' becomes 'z').

Return the final string after all such shifts to s are applied.

Example 1:

Input: s = "abc", shifts = [[0,1,0],[1,2,1],[0,2,1]]

Output: "ace"

Explanation: Firstly, shift the characters from index 0 to index 1 backward. Now s = "zac".

Secondly, shift the characters from index 1 to index 2 forward. Now s = "zbd".

Finally, shift the characters from index 0 to index 2 forward. Now s = "ace".

Example 2:

Input: s = "dztz", shifts = [[0,0,0],[1,1,1]]

Output: "catz"

Explanation: Firstly, shift the characters from index 0 to index 0 backward. Now s = "cztz".

Finally, shift the characters from index 1 to index 1 forward. Now s = "catz".

Solution