Flood Fill

You are given an image represented by an `m x n` grid of integers `image`, where `image[i][j]` represents the pixel value of the image. You are also given three integers `sr`, `sc`, and `color`. Your task is to perform a **flood fill** on the image starting from the pixel `image[sr][sc]`. To perform a **flood fill**: - Begin with the starting pixel and change its color to `color`. - Perform the same process for each pixel that is **directly adjacent** (pixels that share a side with the original pixel, either horizontally or vertically) and shares the **same color** as the starting pixel. - Keep **repeating** this process by checking neighboring pixels of the _updated_ pixels and modifying their color if it matches the original color of the starting pixel. - The process **stops** when there are **no more** adjacent pixels of the original color to update. Return the **modified** image after performing the flood fill.   **Example 1:** **Input:** image = [[1,1,1],[1,1,0],[1,0,1]], sr = 1, sc = 1, color = 2 **Output:** [[2,2,2],[2,2,0],[2,0,1]] **Explanation:** From the center of the image with position `(sr, sc) = (1, 1)` (i.e., the red pixel), all pixels connected by a path of the same color as the starting pixel (i.e., the blue pixels) are colored with the new color. Note the bottom corner is **not** colored 2, because it is not horizontally or vertically connected to the starting pixel. **Example 2:** **Input:** image = [[0,0,0],[0,0,0]], sr = 0, sc = 0, color = 0 **Output:** [[0,0,0],[0,0,0]] **Explanation:** The starting pixel is already colored with 0, which is the same as the target color. Therefore, no changes are made to the image.   **Constraints:** - `m == image.length` - `n == image[i].length` - `1 <= m, n <= 50` - `0 <= image[i][j], color < 216` - `0 <= sr < m` - `0 <= sc < n`