Struct Maze 

struct Maze {
    initial: State,
    masks: [u32; 30],
    minimum: [u32; 30],
    matrix: [[Door; 30]; 30],
}

initial is the complete set of keys that we need to collect. Will always be binary 11111111111111111111111111 for the real input but fewer for sample data.

masks maps the set of keys in the same quadrant, for prefiltering in part 2. minimum is the smallest distance from a key to any of its neighbors, for the part1 heuristic. matrix is the adjacency of distances and doors between each pair of keys and the robots’ starting locations.

Fields

initial: State

masks: [u32; 30]

minimum: [u32; 30]

matrix: [[Door; 30]; 30]