Problem

Given a 2D array representing an image, where image[i][j] is the pixel value at row i and column j, perform a flood fill operation.

Starting from the pixel image[sr][sc], replace the color of this pixel and any 4-directionally connected pixels with the same initial color with color.

Return the modified image.

Examples

/* [
  [2,2,0],
  [2,1,1],
  [0,1,2]
] */
floodFill([[2,2,0],[2,1,1],[0,1,2]], 1, 1, 3)
// [[2,2,0],[2,3,3],[0,3,2]]
/* [
  [2,2,0],
  [2,3,3],
  [0,3,2]
] */
// Why? Starting from (1,1) which is color 1
// we change it and its neighboring pixels with the same color to 3.


floodFill([[0,1,0],[1,1,1],[0,1,0]], 1, 1, 1)
// [[0,1,0],[1,1,1],[0,1,0]]
// Why? The starting pixel and its neighbors are already of color 1.
// So, the image remains unchanged.