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# Kathy's book - chapter 6 - question #7

Mansi Vyas
Greenhorn
Posts: 27
The answer is a, b, and d. What types of implicit conversions are going on for b and d?
Thanks.
Mansi

Corey McGlone
Ranch Hand
Posts: 3271
As not everyone has a copy of the book (including myself), you might find that you get more responses if you were to include the original question in your post.

Damien Howard
Ranch Hand
Posts: 456
I believe that in b 2.3 is truncated to an int value of 2, thus the version of Math.max is the one that takes 2 ints.
And in D the -2.8f is widened to a double, thus in this case the version of Math.max is the one that accepts 2 doubles.

Mansi Vyas
Greenhorn
Posts: 27
Sorry for not including the question. Here it is...
Which of the following are valid calls to Math.max? Choose all that apply.
A. Math.max(1,4)
B. Math.max(2.3, 5)
C. Math.max(1,3,5,7)
D. Math.max(-1.5, -2.8f)
In choice B, I think that the 5 is being implicity converted to a 5.0(double). In choice D, I think that -2.8f is being implicity promoted to a double. Both are invoking the following method signiture, double max(double a, double b).
Is this correct?
Thanks.
Mansi

Andres Gonzalez
Ranch Hand
Posts: 1561
Correct...
The thing to remember here is this order:
byte
short
int
long
float
double
So, for example, in option D. we have a float and a double, so we know that float can be implicitly promoted to a double.
HTH