Thread: Problems Reading Line With Unknown Number of Integers

I need to read a file via stdin (so I'll run my program as ./program <input.txt> output.txt) but I am having problems doing so correctly. The input file starts with an integer x, and x lines follow. Each line starts with an s (for sub-set), followed by an unkown number of integers. So something like this:

Code:

5
s 1 2 5
s 3 7 9 11 13
s 2 4 8 10 12
s 3
s 1 5 8 10 13 15 17

The problem I am facing is to know when to stop, given that each line has an unknown number of integers. I tried this code:

Code:

int main(){
	int i,x,n;
	char c;

	scanf("%d",&x);
	scanf("%c",&c); /*to remove the first line break*/

	for (i=0;i<x;i++){
		scanf("%c",&c); /*process the 's'*/
		while(scanf("%d",&n);){ /*repeat while scanf matches a number*/			
			printf("%d\n",n);
		}		
	}	
	return 0;
}

But it goes into an infinite loop. Somehow the scanf keeps reading the last number of the first line over and over again. I also tried to read the whole line at once, but then I don't know how to separate the numbers from the 's'.

Anyone has a different idea?

That fixed it.

Thanks a lot.