keep doing scanf for all input in command line. C program

Question

I am trying to get all the input from the command line and putting it in a linked list. the numbers from the command line are of this format 0-1 2-3 4-9 etcc Here is what I did to store a pair of numbers in two variables:

scanf("%d-%d", &a, &b);

Now, this scanf statement is inside a loop and my question is: what is the condition of the loop? I want to keep doing scanf until all the input is finished.

Thanks in advance.

Answer 1

A famous, if not notorious characteristic of scanf is that it will leave data in input buffer when reading non-string data(eg, int ). Check out here: Leave data in input buffer .

Try this:

do
{
  int x = scanf("%d-%d", &a, &b);
}while ((x != EOF) && (getchar() != '\n'));

You need to compare scanf output with EOF. And most importantly, you need flush out the '\\n' left by scanf in input buffer.