How to calculate the shortest path between two points using a matrix of numbers?

Question

Programming

I welcome everyone.
I am writing the so-called Lee Algorithm (aka unary / wave search).
In short, the essence is as follows:
We fill the matrix with numbers, moving in a wave from point A to point B.
Example:

In general, I managed to write a function that could fill the matrix in such a way. I used recursive calls for left/right/top/bottom positions and populated the array itself. But the question is: how can I calculate the shortest path now?
PS: I wrote Java code, but it doesn't matter. So you can give an example in any language (but preferably C-like or python).

Answer 1

Starting from the end point, you just always go towards the smallest number.