Cod sursa(job #405846)

Utilizator freak93Adrian Budau freak93 Data 28 februarie 2010 20:07:35
Problema Suma divizorilor Scor 80
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.1 kb
#include<fstream>

using namespace std;

const char iname[]="sumdiv.in";
const char oname[]="sumdiv.out";
const long long mod=9901;

ifstream f(iname);
ofstream g(oname);

long long a,b,i,j,k,rez;

long long powx(long long x,long long y)
{
    if(y==0)
        return 1LL;
    long long v=powx(x,y>>1LL);
    v=v*v;
    v%=mod;
    if(y&1)
        return (v*(x%mod))%mod;
    return v;
}

int main()
{
    f>>a>>b;
    rez=1;
    for(i=2;i*i<=a;++i)
        if(a%i==0)
        {
            j=0;
            while(a%i==0)
            {
                ++j;
                a/=i;
            }
            if(i%mod==1)
            {
                rez*=j*b+1,rez%=mod;
                continue;
            }
            k=((powx(i,j*b+1))+mod-1);
            rez*=k;
            rez%=mod;
            rez*=powx(i-1,mod-2);
            rez%=mod;
        }
    if(a>1)
    {
        k=(powx(a,b+1)+mod-1);
        rez*=k;
        rez%=mod;
        rez*=powx(a-1,mod-2);
        rez%=mod;
    }
    g<<rez<<"\n";

    f.close();
    g.close();

    return 0;
}