Counting objects in binary image

How can I count the number of objects in a binary image without using built in functions? I know that regionprops does that, but I am not allowed to use built in functions.

[KSSV]

Can you attach your image, so that we can help you.

Answer 1

[Image Analyst]

You can probably find connected components labeling pseudocode on the internet somewhere. Of course, if you do find that, could it be considered a "built-in function" that you're not allowed to use since someone else wrote it?