Pathfinding is a common problem that artificial agents must solve, including

mapping services, artificial vehicles, AIs in real$-$time strategy games, and robots that

must navigate in the physical world. For this assignment we will focus on simplified

pathfinding problem. Your program will search for the shortest path from a starting

location to a goal location on a square grid. However, this grid will have some

impassable locations and varying terrain costs that must be accounted for. The

agent is allowed to move in any of the four primary directions $($up$,$ down, left, right$)$

but not diagonally or outside the bounds of the map.