Leetcode Everyday: 832. Flipping an Image. Easy

public class Solution {
    public int[][] FlipAndInvertImage(int[][] image) {
        foreach (var row in image) {
            for (var col = 0; col < row.Length / 2; ++col) {                
                // shorthand:
                (row[col], row[^(col+1)]) = (row[^(col+1)], row[col]);
                
                // longhand:
                // (row[col], row[row.Length - (col+1)]) = (row[row.Length - (col+1)], row[col]);
            }            
            
            for (var col = 0; col < row.Length; ++col) {
                row[col] ^= 1;
            }
        }
        
        return image;
    }
}

Optimized:

public class Solution {
    public int[][] FlipAndInvertImage(int[][] image) {
        foreach (var row in image) {
            var half = row.Length / 2;
            for (var col = 0; col < half; ++col) {                
                // shorthand:
                (row[col], row[^(col+1)]) = (row[^(col+1)] ^ 1, row[col] ^ 1);
                
                // longhand:
                // (row[col], row[row.Length - (col+1)]) = (row[row.Length - (col+1)], row[col]);
            }                        
        }
        
        if (image.Length > 0 && image[0].Length % 2 == 1) {
            var middle = image[0].Length / 2;
            foreach (var row in image) {
                row[middle] ^= 1;
            }
        }
        
        return image;
    }
}

Source: https://leetcode.com/problems/flipping-an-image/