sscanf() double & string

Question

I am fairly new to the world of programming so please forgive me if this is a common mistake.

I'm trying to scan 3 double values and 3 strings out of one input string but it doesnt continue after the second value.

double total_weight_kg(char *s, int Length) {
    double weights[3];
    char units[3];
    int test = sscanf(s, "%lf, %s, %lf, %s, %lf, %s",
                      &weights[0], &units[0],
                      &weights[1], &units[1],
                      &weights[2], &units[2]);
    printf("%i\n", test);
    printf("%s\n", &units[0]);

int main(void) {
    total_weight_kg("5, g, 1, t, 175, kg", 3);
    return 0;

The first print prints out 2 and the second the g.

Furthermore I'd like to compare units[i] in a loop but can't seem to get that working either.

for (int i = 0; i < Length; i++) {
    w = weights[i];
    if (strcmp(units[i], "kg") == 0) {
        weight += w;
    }
}

I hope you can help me find a solution for this problem,

edit: Everyting is working as intended now. Thank you very much for your help. ( 19[^,] was one major problem )

Answer 1

There are some problems in your code:

• To scan the strings into units, you must define it as a 2D array of char:

  char units[3][20];
  

• You should modify the scanf format to stop the word parsing on , and spaces, as suggested by user3386109.

• Also modify the printf to pass the array instead of its address.

Here is the modified code:

double total_weight_kg(char *s, int Length) {
    double weights[3];
    char units[3][20];
    int test = sscanf(s, "%lf, %19[^, \n], %lf, %19[^, \n], %lf, %19[^, \n]",
                      &weights[0], units[0],
                      &weights[1], units[1],
                      &weights[2], units[2]);
    printf("%i\n", test);
    printf("%s\n", units[0]);
   ...
}

int main(void) {
    total_weight_kg("5, g, 1, t, 175, kg", 3);
    return 0;
}