Sortare Divizori

#include <stdio.h>
#include <algorithm>
using namespace std;
FILE *f,*g;
struct sir
{
    int nr;
    int nd;
};
sir a[1000];
int n;

inline bool cmp(sir a,sir b)
{
    if(a.nd==b.nd)
        return a.nr<b.nr;
    else
        return a.nd>b.nd;
}

int nrdiv(int n)
{
    int p=1,d,exp=0; // p retine numarul divizorilor
    if(n%2==0)
    {
        while(n%2==0)
        {
            exp++;
            n=n/2;
        }
        p*=(exp+1);
    }
    d=3;
    while(n>1)
    {
        if(n%d==0)
        {
            exp=0;
            while(n%d==0)
            {
                exp++;
                n=n/d;
            }
            p*=(exp+1);
        }
        else
            d+=2;
        if(n>1&&d*d>n)
        {
            p*=2; // aici exp=1
            break;
        }
    }
    return p;
}

int main()
{
    f=fopen("sortare_divizori.in","rt");
    g=fopen("sortare_divizori.out","wt");
    fscanf(f,"%d",&n);
    for(int i=0;i<n;i++)
    {
        fscanf(f,"%d ",&a[i].nr);
        a[i].nd=nrdiv(a[i].nr);
    }
    sort(a,a+n,cmp);
    for(int i=0;i<n;i++)
        fprintf(g,"%d ",a[i].nr);
    return 0;
}