# 1427. Perform String Shifts

<https://leetcode.com/problems/perform-string-shifts>

## Description

You are given a string `s` containing lowercase English letters, and a matrix `shift`, where `shift[i] = [directioni, amounti]`:

* `directioni` can be `0` (for left shift) or `1` (for right shift).
* `amounti` is the amount by which string `s` is to be shifted.
* A left shift by 1 means remove the first character of `s` and append it to the end.
* Similarly, a right shift by 1 means remove the last character of `s` and add it to the beginning.

Return the final string after all operations.

**Example 1:**

```
**Input:** s = "abc", shift = [[0,1],[1,2]]
**Output:** "cab"
**Explanation:** 
[0,1] means shift to left by 1. "abc" -> "bca"
[1,2] means shift to right by 2. "bca" -> "cab"
```

**Example 2:**

```
**Input:** s = "abcdefg", shift = [[1,1],[1,1],[0,2],[1,3]]
**Output:** "efgabcd"
**Explanation:**  
[1,1] means shift to right by 1. "abcdefg" -> "gabcdef"
[1,1] means shift to right by 1. "gabcdef" -> "fgabcde"
[0,2] means shift to left by 2. "fgabcde" -> "abcdefg"
[1,3] means shift to right by 3. "abcdefg" -> "efgabcd"
```

**Constraints:**

* `1 <= s.length <= 100`
* `s` only contains lower case English letters.
* `1 <= shift.length <= 100`
* `shift[i].length == 2`
* `directioni`is either `0` or `1`.
* `0 <= amounti <= 100`

## ac

```java
```