Application background Given a maze, the entrance is the upper left corner, the outlet is the lower right corner, if there is a path from the entrance to the exit, if there is a way out of this. Note that the move can be from the upper, lower, left, right, left, right, left, right, left, right, eight directions. Maze input 0 that can go, enter the wall 1. Easy to use 1 to avoid boundary problems in the maze. Key Technology The use of BFS algorithm is given. Note that the path given by the BFS algorithm is bound to be one of the shortest paths.