im learning c++ and one the assignments we've been given is to write a program to determine absolute values. theres something wrong with it and i cant figure out what. i know there are a couple techies on the board so hopefully one of you can help me.

#include <iostream.h>

void main()
{

double value, answer;

cout <<"Please enter a value: ";
cin >> value;

if (value = 0);
cout <<"Your number is zero.";

if (value < 0);
cout <<"Your number is positive.";

if (value > 0);
answer = value * -1;
cout <<"The absolute value of " <<value <<" is " <<answer <" . ";
}

this is resurfacing terrible nightmares from college

at least it's not FORTRAN. fuck that shit.

Looks like you have your tests backwards (greater than and less than).

You need double == in your if tests.

A single = is to set a value, a double == is for compares.

yeah your logic is backwards...

also use else ifs (if.....else if.....else...) - moer efficent

instead of 3 separate ifs...

ditto on the == as well

Also, I don't think you want all those semicolons there (at the end of each if).

thanks for the help so far. and thanks for spotting my equals and greater/less than errors. it still wont compile correctly, though. this is the error message it spits out. (i didnt paste the whole thing, just the important part)

It's the semicolon -- take it off the other(s), as well.

oh crap, yeah it was the semi colons that were screwing it up. all right, heres problem number 2.



which leads me to believe im going to have to rewrite it as an if else type thing.

edit: copied and pasted the wrong error.

cout <<"The absolute value of " <<value <<" is " <<answer <" . ";

need another less than

awesome, it works now. thanks everyone!!!

yeah, watch those semi-colons. only supposed to be used at end-of-statement!

[PopTodd]I don't know what the christ any of the above means, but the fact that you all pitched in to help out is one more example of why Obner is A-OK.[/PopTodd]

I'm taking FORTRAN this semester...ugh

fortran's the worst i've seen since assembler language. c++ is close.

i much prefer java's oo approach.

Well Fortran is a requirement for my major, but they are getting rid of it next semester. Will have to learn Java instead.

why would they make you learn fortran? at least c++ is somewhat useful. after youre done learning it you can pretty much throw out everything you learned. what a totally useless and ancient language. just about anything would be better than that. i have a programming friend who learned fortran first, and now never uses it. (because of course, its totally useless)

Fortran is still used quite a bit. Nothing beats it for number-crunching and reuse.

My professor is a full believer in fortran. He's all disheartened that he won't be allowed to teach it anymore after this semester. But I figure if I know that, learn java, and bone up on my c++ (took it years ago), then I'll be ok in the long run.

Java, C++ and especially Visual Basic .NET are the best. Everything else is un-American.