Example from Sun

[Vladimir Kositsky]

7. Given
double pi = Math.PI;
Which two are valid ways to round pi to an int?(Choose two.)
A.int p = pi;
B.int p = Math.round(pi);
C.int p = (int)Math.round(pi);
D.int p = (int)Math.min(pi + 0.5d);
E.int p = (int)Math.floor(pi + 0.5d);

This topic has been discussed last days , i just cannot find thread.
Gonna be B and E???

[Scott Kiel]

Vladimir,
I think b is incorrect. Math.round(double d) returns a long which would require an explicit cast to int as in c.

[nan sh]

i think E is correct too.

[Vladimir Kositsky]

b is corerect for sure, there is two methods , one returns int, second - long.
But what was really interesting for me - second answer, i found it today in class spesifications, it is e.

[Scott Kiel]

I agree the second part is the more interesting but for the first part b does not work. There are two methods for round but as I read the question it is not calling the method that returns an int. It is calling round with an argument that is a double. This returns a long which requires a cast to be squeezed into an int.

[Wahid Sadik]

C is correct.
E is also correct, as Math.floor() also gives 3.

[Wahid Sadik]

Could any one give me the link to Sun's examples we are talking?
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Regards - Wahid
[This message has been edited by Wahid Sadik (edited January 07, 2001).]

[Vladimir Kositsky]

Scott,
you right.
round(double) - Static method in class java.lang.Math
Returns the closest long to the argument.
round(float) - Static method in class java.lang.Math
Returns the closest int to the argument.
Link: http://suned.sun.com/USA/certification/progsqwa.html

[This message has been edited by Vladimir Kositsky (edited January 07, 2001).]

[NILESH PATEL]

I think the answer is C & E.
C, because, without casting result would be 3.00 and with (int) cast result would be 3
E, because, without cast, result would be floor(3.14 + 0.5= 3.64), which equals 3.00 and with cast(int) result would be 3
Agree???
Thanks.
Nielsh