Description
Part 1. In the graph below you see the possible flights between some of the cities in Turkey. Write the
predicate “route(X,Y) – a route between X and Y exists” that returns true of if there is a route between
any given two cities.
Istanbul 
Rize
Van
-
-
Edirne
Izmir
Ankara
Edremit
Isparta
Konya
-
Gaziantep
Erzincan Burdur Antalya
Your program should have all the facts and predicates/rules. See the following:
-
knowledge base
…
flight(istanbul,antalya). % the fact that Istanbul and Antalya has a flight.
…
-
rules
…
route(X,Y) :- flight(X,Y). % a predicate indicating there exist a route between % X and Y if there is flight between X and Y.
…
A single query to complete your program should check if there is a direct route between two given cities. Alternatively, it can list all the connected cities for a given city. See the following:
?- route(edirne,X).
X = erzincan ;
X = edremit ;
Make sure that your predicate implementation handles cycles properly avoiding infinite loops.
Part 2. Continuing with the previous problem, you are asked to write a program that checks if a route exists between two cities and if so, provides the shortest route.
In the first step, you are to expand the knowledge by adding distances for the direct flights. E.g.,
-
knowledge base
…
flight(istanbul, antalya). % the fact that Istanbul and Antalya has a flight. distance(istanbul, antalya, 481). % flight distance – calculated using
-
complete all the flights and distances …
…
A single query to complete your program should check if there is a direct route between two given cities and the shortest distance between them. See the following example:
?- sroute(edremit,erzincan,X).
X=1044;
Part 3. You are given the following database about classes, classrooms and student enrollment.
-
Classes
Enrollment
Class
Time
Room
Student
Class
102
10
z23
a
102
108
12
z11
a
108
341
14
z06
b
102
455
16
207
c
108
452
17
207
d
341
e
455
Write the predicates “when(X,Y) – time of the course X is Y”, “where(X,Y) – place of the course X is Y”, and “enroll(X,Y) – student X is enrolled in course Y”. For example:
-
facts.. when(102,10).
3.1. Define/write a predicate “schedule(S,P,T)” that associates a student to a place and time of class.
See the example query and its result.
?- schedule(a,P,T).
P=102
T=10;
P=108
T=12;
3.2. Define/write another predicate “usage(P,T)” that gives the usage times of a classroom. See the example query and its result.
?- usage(207,T).
T=455;
T=456;
3.3. Define/write another predicate “conflict(X,Y)” that gives true if X and Y conflicts due to classroom or time.
3.4. Define/write another predicate “meet(X,Y)” that gives true if student X and student Y are present in the same classroom at the same time.
Part 4. Write the following predicates operating on sets.
4.1. Define a Prolog predicate “element(E,S)” that returns true if E is in S.
4.2. Define a Prolog predicate “union(S1,S2,S3)” that returns true if S3 is the union of S1 and S2.
4.3. Define a Prolog predicate “intersect(S1,S2,S3)” that returns true if S3 is the intersection of of S1 and S2.
4.3. Define a Prolog predicate “equivalent(S1,S2)” that returns true if S1 and S2 are equivalent sets.
