LeetCode: FloodFill C#

Question

https://leetcode.com/problems/flood-fill/

图像由二维整数数组表示，每个整数表示图像的像素值(从0到65535)。给定表示洪水填充的起始像素(行和列)的坐标(sr，sc)和像素值newColor，“洪水填充”图像。要执行“洪流填充”，请考虑起始像素，再加上与起始像素相同颜色的起始像素4方向连接的任何像素，再加上与这些像素定向连接的任何像素(也与起始像素的颜色相同)，等等。用newColor替换上述所有像素的颜色。最后，返回修改后的图像。

Example 1:
Input: 
image = [[1,1,1],[1,1,0],[1,0,1]]
sr = 1, sc = 1, newColor = 2
Output: [[2,2,2],[2,2,0],[2,0,1]]
Explanation: 
From the center of the image (with position (sr, sc) = (1, 1)), all pixels connected 
by a path of the same color as the starting pixel are colored with the new color.
Note the bottom corner is not colored 2, because it is not 4-directionally connected
to the starting pixel.
Note:

The length of image and image[0] will be in the range [1, 50].
The given starting pixel will satisfy 0 <= sr < image.length and 0 <= sc < image[0].length.
The value of each color in image[i][j] and newColor will be an integer in [0, 65535].

请检查性能和编码风格。

using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace ArrayQuestions
{
    /// <summary>
    /// https://leetcode.com/problems/flood-fill/
    /// </summary>
    [TestClass]
    public class FloodFillTest
    {
        [TestMethod]
        public void ExampleTest()
        {
            int[][] image = { new[] { 1, 1, 1 }, new[] { 1, 1, 0 }, new[] { 1, 0, 1 } };
            int sr = 1;
            int sc = 1;
            int newColor = 2;
            int[][] expected = { new[] { 2, 2, 2 }, new[] { 2, 2, 0 }, new[] { 2, 0, 1 } };
            FloodFillDFS dfs = new FloodFillDFS();
            dfs.FloodFill(image, sr, sc, newColor);
            for (int i = 0; i < 3; i++)
            {
                CollectionAssert.AreEqual(expected[i],image[i] );
            }

        }
    }

    public class FloodFillDFS
    {
        public int[][] FloodFill(int[][] image, int sr, int sc, int newColor)
        {
            int oldColor = image[sr][sc];
            DFS(image, sr, sc, newColor, oldColor);
            return image;
        }

        //make sure to check first the corner cases
        private void DFS(int[][] image, int sr, int sc, int newColor, int oldColor)
        {
            if (sr < 0 || sc < 0 || sr >= image.Length || sc >= image[0].Length || image[sr][sc] == newColor || image[sr][sc] != oldColor)
            {
                return;
            }

            image[sr][sc] = newColor;
            DFS(image, sr - 1, sc, newColor, oldColor);
            DFS(image, sr + 1, sc, newColor, oldColor);
            DFS(image, sr, sc - 1, newColor, oldColor);
            DFS(image, sr, sc + 1, newColor, oldColor);
        }
    }
}

Answer 1

我会将if除以3个变量，并给每个变量取一个名称: out映像、isVisited和isOriginalColor或类似的名称。

我不知道sr是什么意思，我会用行和行。

FloodFill返回图像，但是dfs改变了原始图像，它会混淆类的用户。