Cod sursa(job #3256323)

Utilizator rapidu36Victor Manz rapidu36 Data 14 noiembrie 2024 09:54:14
Problema Suma divizorilor Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.7 kb
#include <fstream>

using namespace std;

const int MOD = 9901;

int indicatorul_euler(int n)
{
    int e = n, d = 2;
    while (d * d <= n)
    {
        if (n % d == 0)
        {
            e = e / d * (d - 1);
            while (n % d == 0)
            {
                n /= d;
            }
        }
        d++;
    }
    if (n != 1)
    {
        e = e / n * (n - 1);
    }
    return e;
}

int putere(int a, int n)
{
    a %= MOD;
    int p = 1;
    while (n != 0)
    {
        if (n % 2 != 0)
        {
            p = (p * a) % MOD;
        }
        a = (a * a) % MOD;
        n /= 2;
    }
    return p;
}

int invers(int a, int fi)
{
    return putere(a, fi - 1);
}

int main()
{
    ifstream in("sumdiv.in");
    ofstream out("sumdiv.out");
    int a, n;
    in >> a >> n;
    int d = 2, sum = 1, fi = indicatorul_euler(MOD);
    while (d * d <= a)
    {
        if (a % d == 0)
        {
            int p = 0;
            while (a % d == 0)
            {
                p++;
                a /= d;
            }
            if (d % MOD != 1)
            {
                sum = ((long long)sum * (putere(d, p * n + 1) - 1 + MOD) * invers(d - 1, fi)) % MOD;
            }
            else
            {
                sum = ((long long)sum * (p * n + 1)) % MOD;
            }
        }
        d++;
    }
    if (a != 1)
    {
        if (a % MOD != 1)
        {
            sum = ((long long)sum * (putere(a, n + 1) - 1 + MOD) * invers(a - 1, fi)) % MOD;
        }
        else
        {
            sum = ((long long)sum * (n + 1)) % MOD;
        }
    }
    out << sum;
    in.close();
    out.close();
    return 0;
}