problema rucsacului greedy

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

typedef struct
{
    int id;
    double greutate, castig;
}Obiect;

int cmpObiecte(const void *a, const void *b) // ord descr
{
    Obiect va = *(Obiect *)a;
    Obiect vb = *(Obiect *)b;

    if (va.castig /va.greutate < vb.castig / vb.greutate)
        return 1;

    if (va.castig /va.greutate > vb.castig / vb.greutate)
        return 0;
}


int main()
{
    int n,i;
    double G, ct, auxG, p;

    Obiect *ob;
    FILE *fin, *fout;
    fin = fopen("rucsac.in","r");

    fscanf(fin,"%d",&G);
    fscanf(fin,"%d",&n);

    ob = (Obiect*) malloc(n*sizeof(Obiect));

    for (i=0; i<n; i++)
    {
        ob[i].id = i+1;
        fscanf(fin,"%d %d",&ob[i].castig,&ob[i].greutate)
    }

    fclose(fin);

    qsort(ob,n,sizeof(Obiect),cmpObiecte);
    auxG = G;
    ct = 0;
    for (i=0; i<n; i++)
        if(ob[i].greutate <= auxG)
    {
        printf("obiectul %d: 100%%\n",ob[i].id);
        ct = ct + ob[i].castig;
        auxG = auxG - ob[i].greutate;
    }
    else
    {
        p = auxG/ob[i].greutate;
        printf("obiectul %d: %.2f%%\n",ob[i].id,p*100);
        ct = ct + p * ob[i].castig;
        auxG = 0;
        break;
    }

    printf("Castigul total este: %d\n",ct);
    fclose(fout);

    free(ob);

    return 0;
}