Given a 2D image and a starting pixel, recolor the entire connected region of the starting pixel using four-directional adjacency and return the updated image. Pattern focus: Flood fill. Traverse one connected component and paint it with the new color.
image = 2D integer matrix, sr/sc = start cell, color = new color
updated image after 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:
The connected component containing (1,1) is recolored from 1 to 2.
Example 2:
Input:
image = [[0,0,0],[0,1,1]] sr = 1 sc = 1 color = 1
Output:
[[0,0,0],[0,1,1]]
Explanation:
The new color is the same as the old color, so the image remains unchanged.
Example 3:
Input:
image = [[0]] sr = 0 sc = 0 color = 7
Output:
[[7]]
Explanation:
A single pixel is recolored.