multiple inputs by user dynamically at runtime

Question

How can we take multiple number of integer inputs by user choice in c in runtime. Here the first line of the input is the number of test cases. Then I am calculating the sum of the input numbers in this case.

The test case :

Input

Output:

14
16
3

Can we modify scanf() in this way so it can process this dynamic inputs.

I can't take the line as a string input and then split them into numbers.

Can we use the space and \n both to decide the numbers as we do to take strings as input as an example: scanf("%[^\n]",&str);

`scanf("%d",&num)` will do the trick. But do you know how many numbers will be inputted in each test case? or is it random? — Spikatrix, May 08 '15 at 13:47
*"I can't take the line as a string input and then split them into numbers."* — why is the obvious solution not allowed? — r3mainer, May 08 '15 at 13:52
I was trying to use variable arguments in c, but failed, I use that technique not string @squeamishossifrage — Subinoy, May 08 '15 at 13:53
scanf has already variable arguments, but you need to know, at least, the number of arguments to prepare the format string. Otherwise you have to get it by string and split values. — LPs, May 08 '15 at 14:01
@Subinoy , Are the numbers in the test cases always seperated by one space? If yes, then I have a solution that doesn't involve strings at all. — Spikatrix, May 08 '15 at 14:02
You can do what you want, but I don't know how, if you want a random number of inputs... — LPs, May 08 '15 at 14:02
@haccks , Did you get notified by my earlier(deleted) comment? — Spikatrix, May 08 '15 at 15:40

score 1 · Accepted Answer · answered May 25 '15 at 10:45

The answer was provided by BLUEPIXY by his nice code. Here we will consider inputs as a pair.

Either it will be a pair of number and space or it will be a pair of number and newline character.

Example: 2 3 4

So in this input we take as pairs, like - '2', '3' and '4\n'. When we encounter a \n we stop the infinite loop. Here the code goes:

#include <stdio.h>

int main(void){
    int n;

    scanf("%d", &n);
    while(n--){
        int v, sum = 0;
        while(1){
            char ch = 0;
            scanf("%d%c", &v, &ch);
            sum += v;
            if(ch == '\n' || ch == 0)
                break;
        }
        printf("%d\n", sum);
    }

    return 0;
}

Inputs:

Output:

14
16
3

Minor holes with this approach is that it relies on 1) the `'\n'` following number and 2) line has at least 1 number 3) input text is always numeric. — chux - Reinstate Monica, Nov 06 '15 at 14:40
@chux Yeah you are right that the input text is always need to be numeric. — Subinoy, Jan 11 '16 at 17:58

multiple inputs by user dynamically at runtime

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