Thread: help I'm lost

I have a really weird problem with my code. it all looks fine to me, but when I input x it starts with a completely different number e.g. when I put in -15 it starts at 45. Can someone see the problem?

Code:

main()
{
 int c,x,y,count=0;

 printf("Enter the starting variable:");
 x=getchar();

 for(count=0;count<50;count++,x++)
  {
    c=(x/((x%10)+1))%x;
    y=(x-c)%50;
    printf("X=%d		Y=%d\n",x,y);
    if(count%10==0)
      getch();
  }
 getch();
 return 0;
}

you are getting a char from the keyboard, not int, use atoi to your char scanf a int.

thanks, looks like I forgot about atoi().
I guess it's been too long since I programmed something

to use scanf all I do is this
scanf("%d", &intvar);
while(getchar() != '\n');

that works for me, that isn't so hard.

what is wrong with that, I know I could error check it, but then what is wrong, why not use scanf?

okay, I have one more question. It's the same program, but different topic. Maybe this just isnt' my day to program something, but I'm trying to do some file writing, and the K&R book's explanation of fprintf() isn't making enough sense to me. I've never used fprintf, just ones like fwrite() and fputc(). Can I use fprintf() in the same way as printf()?

nevermind, I answered my own questoin.

Originally posted by Prelude

....input poorly and scanf should be avoided unless you know what you're doing (which few do)......

This sounds interesting - you are saying then that there are ways that scanf can be safely used? Are you aware of anyone who covers this topic in depth? (either online or in a book) I would be interested in learning more some time about the whole scanf thing, its dangers and its usefulness.

kermit

Wait a second - I should have read one of the previous posts more carefully - a link to Summit's FAQ... I should read whats there first possibly...