run-time error :(
Why do this code get a run-time error ?
Thanks alot!
Code:#include <stdio.h> #include <math.h> int main(int argc, char *argv[]) { int num,i,root; float j=1; printf("Enter a 3 digit number\n"); scanf("%d",num); root=sqrt(num); for (i = 2; j!=2 && i<=root; i++) { if (num%i==0) { j++; } } if (j==2) printf("%d is a prime number",&num); else printf("%d is not a prime number",&num); system("PAUSE"); return 0; }
scanf requires a pointer for an argument, a la scanf("%d", &num).
Thank you!!
you are a genius!!!
OK, come on now. tabstop is certainly well versed in C and C++, but "genius"....? lolOriginally Posted by Livnat
Mainframe assembler programmer by trade. C coder when I can.
Todd, you're a genius too.
Well then... with that, I think I'll take the rest of the week off, starting at 5pm today. woo-hoo!Todd, you're a genius too.
(Thanks rob - you're easily impressed too it seems!)
(edit - And, this was my 1,000th post too... This is a special day.)
Mainframe assembler programmer by trade. C coder when I can.
I need to find a way to abduct tabstop and Todd Burch and make them my slaves, muahhaha!Todd, you're a genius too.
By the way, Livnat, if you did not notice, although scanf() requires pointer arguments, printf() does not, especially when the format specifier is %d instead of %p.
Look up a C++ Reference and learn How To Ask Questions The Smart Way
Just remember: it takes a super-devious plan to abduct geniuses, since we can see right through the merely devious plans!
Or cookies. Either way.
Note that using a float variable for a flag to indicate whether or not a divisor is found is not a very good idea. First of all, comparing a float with an integral like 2 might not work properly, because of the way floating point numbers are represented. And then, of course, you're using extra memory because a float takes up more space than, say, an int.
In other words, I would probably use an int (or a bool, if you feel C99-ish), and set it to either 0 (false) or 1 (true). Something like this.
Code:int found = 0; while(found == 0) { /* ... */ found = 1; /* ... */ } if(found == 1) puts("found");
dwk
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Wow... This forum is great!
Thank you all!
I think I'll be around during this semester...
