How do I sort a linked list of structures by one of the fields?

Question

Wow now i know I dont. Lol.

I\'ve got my structure like this:

struct Medico{ 
int Id_Doctor;
int Estado;
char Nombre[60]; ////focus on this part of t         


        

Answer 1

If you want to sort an array of structures, you can use the qsort function, see man qsort. It takes a base address of the array, number of elements, element size and comparing function:

int compare(const void *a, const void *b) {
    Medico *medA = (Medico*) a;
    Medico *medB = (Medico*) b;
    return /* compare medA and medB */;
}

Medico *medicos = /* initialize */;
qsort(medicos, numberOfMedicos, sizeof(Medico), compare);

D’oh, just now I noticed the next-record pointer that probably makes this answer useless. (I’ve changed the question title to make the linked list apparent.) To make at least something from this answer, you can always copy the list into an array:

Medico *medicos = calloc(sizeof(Medico), numberOfMedicos);
Medico *current = /* first record in your linked list */;
int i = 0;

assert(current);
do {
    medicos[i++] = *current;
    current = current->next;
} while (current);

// Here you can sort the array.

free(medicos);

Of course, it depends on the number of records and other variables.

(My C is a bit rusty, feel free to fix.)