Thread: For loop help...

Need a quick advice on the FOR loop (im new)...
I need my loop to, basically, loop until a certain number/character is entered (let's assume it's "0" ).
My immediate thought was to do it this way:

Code:

#include <stdio.h>

int main ( )
{
  int i, choice;
  choice = 1;

  for (i = 0; choice != 0; i++)
  {
    printf("Enter a number: ");
    scanf("%d", &choice);
  }
  printf("You've entered a 0. Exiting the loop...");
}

The loop does work, but while compiling the program i get a warning that i is assigned a value that is never used. No matter what i try i just cant find a way around it, although i have this feeling its quite simple...
Please help....

try a do while loop instead. for loops are usually used for iterations, like counting.

Yaps, just like i thought - the solution was quite simple... I just didnt think "outside the box" (was trying to make it work with the for loop)

Thanx

also:

Code:

  for (; choice != 0;)
  {
    printf("Enter a number: ");
    scanf("%d", &choice);
  }

Whoa, didnt know this little trick... Thanx a lot... I like the for loop a lot more than the while loop for some reason, so its good news

Code:

> for (; choice != 0;)

I never knew you could do this . Mind explaining what the ; does ? This could be a replacement for all while loops than.

Originally Posted by ICool

Mind explaining what the ; does ?

it's part of the syntax for the for loop. it's needed to delimit the different areas of the for loop.

this is an infinite loop:

Code:

for(;;) { do something }

This could be a replacement for all while loops than.

yes. the while loop and for loop and do while loops are there so that the code can be more readable. but you can make code that acts like one loop but uses another.