The main challenge in motion planning is when a robot exists within a particular environment. The robot needs to plan a strategy to reach its destination, starting from point S and reaching point G$,$ as illustrated in the following figure.

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$0$

S

$1$

$2$

$3$

$4$

G

The start state in this problem can be represented as $(0,0)$ and the goal state is represented as $(4,5).$ The agent can perform four possible actions, e$.$g$.,$ Move$-$Up$,$ Move$-$Down, Move$-$Left, and Move Right. The agent can move to white cells, while black cells act as obstacles and cannot be traversed. For example, the agent from the start state $(0,0)$ can perform Move$-$Right or Move$-$Down actions to get into $(0,1)$ or $(1,0)$ states, respectively. The cost of each action is $1,$ representing the actual cost $$g$$ to go from one state to another state. For instance, as the agent moves from state $(0,0)$ to $(0,1)$ with a cost of $1,$ and then from $(0,1)$ to $(1,1)$ with an additional cost of $1,$ the total cost from the start state $(0,0)$ to $(1,1)$ denoted as g$((1,1))$ which is $2.$