Cod sursa(job #1928098)

Utilizator Bodo171Bogdan Pop Bodo171 Data 15 martie 2017 20:51:22
Problema Suma divizorilor Scor 40
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.3 kb
#include <iostream>
#include <fstream>
#include <cmath>
#include <cassert>
using namespace std;
const long long mod=9901;
long long p2,A,B,c,pr[30],pu[30],prod,fix,k,sum,i,t,fact,moda,proda,p2a;
long long p;
int expo(long long a,long long b)
{
     p2=a%mod;prod=1;moda=9901*9901;proda=1;p2a=a%moda;
     for(p=0;(1LL<<p)<=b;p++)
     {
         if(((1LL<<p)&b))
            prod=(1LL*prod*p2)%mod,proda=(1LL*proda*p2a)%moda;
         p2=(1LL*p2*p2)%mod;
         p2a=(1LL*p2a*p2a)%moda;
     }
     return prod;
}
int main()
{
    ifstream f("sumdiv.in");
    ofstream g("sumdiv.out");
    f>>A>>B;
    fix=sqrt(A);c=2;
    while(A!=1)
    {
        if(A%c==0)
        {
            k++;pr[k]=c;
            while(A%c==0)
            {
                A/=c;
                pu[k]++;
            }
        }
        if(c>fix&&A!=1)
        {
            k++;
            pr[k]=A;
            pu[k]=1;
            A=1;
        }
        c++;
    }
    sum=1;
    for(i=1;i<=k;i++)
    {
        t=pr[i]-1;
        while(t%mod==0)
            t/=mod;
        fact=(expo(pr[i],1LL*(B*pu[i]+1))-1)%mod;
        if(fact<0) fact+=mod;
        sum=(sum*fact)%mod;
        sum=(sum*expo(t,mod-2))%mod;
        if(proda==1) {g<<'0';return 0;}
    }
    g<<sum;
    return 0;
}