Printing char value using reference

Question

I'm having trouble trying to printf() a char variable.

I declare two arrays, one for the brand names and the other for the values, based on which value is the biggest I get the appropriate brand name based on the position in the array.

Well, printing marca here works perfectly. But when I try to print it outside the function it doesn't.

Any idea?

Minimal reproducible example:

#include <stdio.h>
#include <string.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>

void fabricanteDeModa(char *);

int main()
{
    char marca;
    fabricanteDeModa(&marca);
    printf("%s", marca); //Not working (already tried changing to %c)

    return 0;
}

void fabricanteDeModa(char *marca)
{
    int apple = 5;
    int xiaomi = 10;
    int samsung = 7;
    int htc = 12;
    int lg = 15;
    int zte = 10;
    int nokia = 2;

    char marcas[7][10] = {
        "apple",
        "xiaomi",
        "samsung",
        "htc",
        "lg",
        "zte",
        "nokia"
    };

    int valores[7] = { apple, xiaomi, samsung, htc, lg, zte, nokia };
    int i;
    int maxVal = valores[0];
    int pos = 0;

    for (i = 1; i < 7; ++i)
    {
        if (valores[i] > maxVal)
        {
            maxVal = valores[i];
            // Find the index of the max value
            pos = i;
        }
    }
    marca = marcas[pos];
    printf("%s\n", marca); //This Works
}

Answer 1

marca should be defined as a char * or better const char * and fabricanteDeModa should return the brand name, not take a pointer to char as posted.

To return the string, the array marcas should not be a 2D array of char with automatic storage (non-static local variable) whose elements will not be accessible after the function returns, you can instead use an array of string pointers.

Here is a modified version:

#include <stdio.h>

const char *fabricanteDeModa(void);

int main() {
    const char *marca = fabricanteDeModa();
    printf("%s\n", marca);
    return 0;
}

const char *fabricanteDeModa(void) {
    int apple = 5;
    int xiaomi = 10;
    int samsung = 7;
    int htc = 12;
    int lg = 15;
    int zte = 10;
    int nokia = 2;

    const char *marcas[7] = { "apple", "xiaomi", "samsung", "htc", "lg", "zte", "nokia" };
    int valores[7] = { apple, xiaomi, samsung, htc, lg, zte, nokia };
    int i;
    int maxVal = valores[0];
    int pos = 0;

    for (i = 1; i < 7; ++i) {
        if (valores[i] > maxVal) {
            maxVal = valores[i];
            // Update the index of the max value
            pos = i;
        }
    }
    printf("Largest element = %d\n", pos);
    printf("La marca de moda es : %s\n", marcas[pos]); //This Works
    return marcas[pos];
}