# Perform String Shifts

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

1. `direction` can be `0` (for left shift) or `1` (for right shift).
2. `amount` is the amount by which string `s` is to be shifted.
3. A left shift by 1 means remove the first character of `s` and append it to the end.
4. 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. `1 <= s.length <= 100`
2. `s` only contains lower case English letters.
3. `1 <= shift.length <= 100`
4. `shift[i].length == 2`
5. `0 <= shift[i] <= 1`
6. `0 <= shift[i] <= 100`

## Solution – Easy to understand

C# Program

```public class Solution {
public string StringShift(string s, int[][] shift) {
int sum = 0;
foreach(int[] arr in shift)
{
if(arr == 0){
sum = sum - arr;
}
else{
sum = sum + arr;
}
}

int len = s.Length;

//To order length below string length
if(sum > len || -sum > len){
sum = sum % len;
}

if(sum > 0){
//Performing right reversal
int d = len - sum;
string result = s.Substring(d) + s.Substring(0,d);
return result;
}
else if(sum < 0){
//Performing left reversal
sum = Math.Abs(sum);
string result = s.Substring(sum) + s.Substring(0,sum);
return result;
}
return s;
}
}
```

## Code Walk Through

Time Complexity: O(n)

Space Complexity: O(1)

## One thought on “Perform String Shifts”

1. Nicholas Diab says:

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