Problem $1$: Path Planning

Given the following discrete map, where:

$R$ denotes the robot's initial position

$1$ denotes an inaccessible cell

$2$ denotes the goal position

Use the Wavefront algorithm to update the map by propagating its FOUR neighbors for each cell, and

then find a path from the robot's initial position to the goal position. Highlight the path.

$($a$)$

$($b$)$ Please fill out the whole table first four neighbors for each cell.