Hi, I have no prior programming experience and am teaching myself C through this book. I am trying to get this program to work. Here it is:
The screen at the bottom of the compiler (Bloodshed Dev-C++) says:Code:#include <math.h> main() { int a; a=pow(3,2); /*I don't know why this doesn't work*/ printf("%d",a); }
[Warning] converting to 'int' from 'double'
The line I commented on is highlighted in red in the compiler. The program is to raise 3 to the power of 2.
Thanks!
The message says the pow() funtion returns a data type of double, not int.
Mainframe assembler programmer by trade. C coder when I can.
Originally Posted by Dino
Thanks. Is there is another function I can use to return an int? Alternatively, if there's some better way to fix it, I'm appreciative of any suggestions.
You can cast the pow() function to return an int.
Mainframe assembler programmer by trade. C coder when I can.
How do you do that?
Try that.Code:a = (int) pow(3,2);
Thanks everyone. I got it to work by doing what I've posted below. Is that part at the top correct (with the two #includes)? I did it because after I followed blurx's suggestion it highlighted the printf line and said printf was undeclared. As you can see, I started to learn C 2 or 3 days ago, so I'm appreciative of all the help.
Code:#include <math.h> #include <stdio.h> main() { int a; a = (int) pow(3,2); /*This works now.*/ printf("%d",a); getchar(); }
Last edited by newbcore; 11-29-2008 at 10:46 PM.
Also, why does this work?
Because pow() function returns double and
you are casting it int.[Note that this may result in loss of precision if arguments
supplied in pow are double].
Also main returns int.
implicit main should not be used.
http://faq.cprogramming.com/cgi-bin/...&id=1043284376
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