Question

I tried the search function but only found questions regarding reading in comma/space delimited files.

My question is however, how do you usually approach this. Say I have a list/array/… of values, like {1, 2, 3, 4} and want to print them with a delimiter.

The simplest version would be something like:

#include <stdio.h>

int main(void)
{
     char list[] = {1, 2, 3, 4};
     unsigned int i;

     for (i = 0; i < 4; ++i)
     printf("%d, ", list[i]);

     return 0;
}

which will obviously print “1, 2, 3, 4, “. The problem I have with that is the comma and space character at the end.

Now I could do:

#include <stdio.h>

int main(void)
{
    char list[] = {1, 2, 3, 4};
    unsigned int i;

    for (i = 0; i < 4; ++i)
    {
        printf("%d", list[i]);
        if (i < 3)
            printf(", ");
    }

    return 0;
}

Bút that doesn’t seem like the best way to do it. Can somebody point me into the right direction? Thanks

PS: No, I don’t usually hardcode values
PPS: No, I am not trying to write .csv files 😉

Answer 1

I use this idiom:

assert(n > 0);
printf("%d", list[0]);
for (i = 1; i < n; ++i)
     printf(", %d", list[i]);

Its one disadvantage is that it doesn’t scale nicely for n == 0, like a simple loop. Alternatively, you can add protection against n == 0:

if (n > 0)
    printf("%d", list[0]);
for (i = 1; i < n; ++i)
     printf(", %d", list[i]);