// Abstract ------------------------------------------------------------------------------------------------------------------------------

This sample is based on Michael Spivey's book "Introduction to logic programming":

- a motel suite has two rooms: lounge, bedroom
- each of the rooms has one door and one window
- the lounge's window needs to be opposite to the door
- the bedroom's door needs to be adjacent to the lounge's door
- the bedroom's window needs to be adjacent to the bedroom's door
- the bedroom's window needs to be on the east wall

Where should the doors and the windows be?

// Examples ------------------------------------------------------------------------------------------------------------------------------

?- #suite(:ld,:lw,:bd,:bw)
-> ( east , west , north , east ) := 1.00 (0.004) 1
-> ( east , west , south , east ) := 1.00 (0.005) 2
-> ( west , east , north , east ) := 1.00 (0.005) 3
-> ( west , east , south , east ) := 1.00 (0.006) 4

 
// Code ----------------------------------------------------------------------------------------------------------------------------------

// opposite walls
opposite {

    (north,south);
    (south,north);
    (east,west);
    (west,east);

}

// adjacent walls
adjacent {

    (north,east);
    (north,west);
    (south,east);
    (south,west);
    (east,north);
    (east,south);
    (west,north);
    (west,south);

}

// describe the lounge constraints
lounge {

    (:ld,:lw,:bd) :- #opposite(:ld,:lw), #adjacent(:ld,:bd);

}

// describe the bedroom constraints
bedroom {

    (:bd,east) :- #adjacent(:bd,east);

}

// describe the suite constraints
suite {

    (:ld,:lw,:bd,:bw) :- #lounge(:ld,:lw,:bd), #bedroom(:bd,:bw);

}

// ---------------------------------------------------------------------------------------------------------------------------------------

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