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

• `direction` can be `0` (for left shift) or `1` (for right shift).
• `amount` 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
0 <= shift[i][0] <= 1
0 <= shift[i][1] <= 100``````

Solution:

``````func stringShift(s string, shift [][]int) string {
sumRight := 0
for _,v := range shift {
switch v[0]{
case 0:
sumRight = sumRight - v[1]
case 1:
sumRight = sumRight + v[1]
}
}
rs := []rune(s)
result := []rune{}
sumRight = sumRight % len(s)
shiftPoint := 0
switch {
sumRight > 0:
shiftPoint = lenS - sumRight
default:
shiftPoint = -sumRight
}
result = append(result, rs[shiftPoint: ]... )
result = append(result, rs[0: shiftPoint]...)

return  string(result)
}``````