11. Write a Prolog program to implement maxlist(List,Max) so that Max is the greatest number in the list of numbers List.
max([H|T],R):-
length(T,L),
L>0 -> ( max(T,R1), ( H > R1 -> R is H ; R is R1 ) ) ; R is H.
OUTPUT:
max([6,9,7],X).
X = 9
max([6,9,70],X).
X = 70
10. Write a Prolog program to implement max(X,Y,Max) so that Max is the greater of two numbers X and Y.
max(X,Y,R):-
X>=Y ->
R is X,
write(R)
;
R is Y,
write(R).
OUTPUT:
max(2,6,X).
6
X = 6
12. Write a Prolog program to implement sumlist(List,Sum) so that Sum is the sum of a given list of numbers List.
sumlist([],0).
sumlist([H|T],R):-
sumlist(T,R1),
R is H+R1.
OUTPUT:
sumlist([6,9,70],X).
X = 85
14. Write a Prolog program to implement reverse(List,ReversedList) that reverses lists.
reverse([],[]).
reverse([X|T],REV):-reverse(T,R),append(R,[X],REV).
OUTPUT:
reverse([1,2,2],X).
X = [2, 2, 1]
13. Write a Prolog program to implement two predicates evenlength(List) and oddlength(List) so that they are true if their argument is a list of even or odd length respectively.
evenlength:-
write('true --> even').
oddlength:-
write('true --> odd').
oddeven([_|T]):- length(T,L), L>=0 -> ( L1 is L+1, L2 is mod(L1,2), L2=:=0 ->evenlength ; oddlength ).
OUTPUT:
oddeven([5,8,9]).
true
--> odd
1true
oddeven([5,8,6,9]).
true
--> even
1true
8. Write a Prolog program to implement append for two lists.
app([],L,L).
app([X|M],N,[X|Q]):-
app(M,N,Q).
OUTPUT:
app([1,2],[3,4],X).
X = [1, 2, 3, 4]
app([1,2],[],X).
X = [1, 2]
7. Write a Prolog program, remove-nth(Before, After) that asserts the After list is the Before list with the removal of every n‘th item from every list at all levels.
del(1,[_|T],T).
del(P,[X|Y],[X|R]):-
P1 is P-1,
del(P1,Y,R).
dalpos(P,L,R):-
P1 is P-1,
del(P1,L,R1),
del(P,R1,R).
OUTPUT:
del(2,[10,20,30,40],X).
X = [10, 30, 40]
Next101001,000 Stop
9. Write a Prolog program to implement palindrome (List).
pal([]):- write('palindrome').
pal([_]):- write('palindrome').
pal(L) :-
append([H|T], [H], L),
pal(T) ;write('Not a palindrome').
OUTPUT:
pal([1,2,1]).
palindrome
1true
Next101001,000 Stop
pal([1,2,2]).
Not
a palindrome
1true
6. Write a Prolog program to remove the Nth item from a list.
del(1,[_|T],T).
del(P,[X|Y],[X|R]):-
P1 is P-1,
del(P1,Y,R).
OUTPUT:
del(2,[1,2],X).
X = [1]
Next101001,000 Stop
del(3,[1,2,3,4],X).
X = [1, 2, 4]
Next101001,000 Stop
del(5,[1,2,3,4],X).
false
5. Write a prolog program, insert_nth(item, n, into_list, result) that asserts that result is the list into_list with item inserted as the n‘th element into every list at all levels.
insert_nth(Item,1,List,[Item|List]).
insert_nth(Item,Pos,[H|List],[H|Result]):-Pos1 is Pos-1,insert_nth(Item,Pos1,List,Result).
OUTPUT:
4. Write a prolog program to calculate the nth Fibonacci number.
fib(0, 1) :- !.
fib(1, 1) :- !.
fib(N, F) :- N > 1, N1 is N-1, N2 is N-2, fib(N1, F1), fib(N2, F2), F is F1+F2.
OUTPUT:
3. Write a prolog program to calculate the factorial of a given number.
fact(0,1).
fact(N,F):-( N>0, N1 is N-1, fact(N1,F1), F is N*F1).
OUTPUT:
fact(5,N).
N = 120
Next101001,000 Stop
2. Write a prolog program to find the maximum of two numbers.
max(X,Y):-( X=Y ->write('both are equal') ;
X>Y -> ( Z is X, write(Z), write(' is max') )
;
( Z is Y, write(Z),write(' is max') ) ).
max(50,50).
both
are equal
1true
max(50,5).
50is max
1true
1. Write a prolog program to calculate the sum of two numbers.
sum(X,Y):-S is X+Y,write(S).
OUTPUT:
The AWT classes are contained in the java.awt package. It is one of Java’s largest packages. Fortunately, because it is logically organized in a top-down, hierarchical fashion.
Event Listener Interfaces
event model has two parts: sources and listeners.
Listeners are created by implementing one or more of the interfaces defined by the java.awt.event package. When an event occurs, the event source invokes the appropriate method defined by the listener and provides an event object as its argument.
The TextEvent Class Instances of this class describe text events. These are generated by text fields and text areas when characters are entered by a user or program. TextEvent defines the integer constant TEXT_VALUE_CHANGED.
The one constructor for this class is shown here: TextEvent(Object src, int type) Here, src is a reference to the object that generated this event. The type of the event is specified by type.
Here, src is a reference to the component that generated the event. The system time at which the mouse event occurred is passed in when.
The modifiers argument indicates which modifiers were pressed when a mouse event occurred. The coordinates of the mouse are passed in x and y. The click count is passed in clicks.
The triggersPopup flag indicates if this event causes a pop-up menu to appear on this platform.
Two commonly used methods in this class are getX( ) and getY( ).
These return the X and Y coordinates of the mouse within the component when the event occurred.
Point getPoint( ) It returns a Point object that contains the X,Y coordinates in its integer members: x and y.
The translatePoint( ) method changes the location of the event. Its form is shown here: void translatePoint(int x, int y) Here, the arguments x and y are added to the coordinates of the event.
The getClickCount( ) method obtains the number of mouse clicks for this event. Its signature is shown here: int getClickCount( )
The isPopupTrigger( ) method tests if this event causes a pop-up menu to appear on this platform. Its form is shown here: boolean isPopupTrigger( )
int getButton( ) It returns a value that represents the button that caused the event. The return value will be one of these constants defined by MouseEvent:
NOBUTTON
BUTTON1
BUTTON2
BUTTON3
The NOBUTTON value indicates that no button was pressed or released. Java SE 6 added three methods to MouseEvent that obtain the coordinates of the mouse relative to the screen rather than the component.
They are shown here:
Point getLocationOnScreen( )
int getXOnScreen( )
int getYOnScreen( )
The getLocationOnScreen( ) method returns a Point object that contains both the X and Y coordinate. The other two methods return the indicated coordinate
