Flood Fill Region Replacement

Problem

Flood fill a 2D image starting from (sr, sc) using 4-connectivity.

Replace every pixel connected to the start whose value equals the starting value with new_color. Return the resulting image; if the start value already equals new_color, return an unchanged copy.

Hint

Use a stack of pixel coordinates; check bounds and equality before pushing.

Test cases

case 1

in: [[[1,1,0],[1,0,0],[0,0,1]],0,0,2]

expected: [[2,2,0],[2,0,0],[0,0,1]]

case 2

in: [[[1,1]],0,0,1]

expected: [[1,1]]

case 3

in: [[[1,0],[0,1]],0,0,9]

expected: [[9,0],[0,1]]

case 4

in: [[[1,1,1],[1,0,0],[1,0,0]],1,2,5]

expected: [[1,1,1],[1,5,5],[1,5,5]]

Starter codePython

def flood_fill(image, sr, sc, new_color):
    # Your code here
    pass

4 test cases · run your code against them in the editor