Cod sursa(job #2092337)

Utilizator andreistanStan Andrei andreistan Data 21 decembrie 2017 15:54:52
Problema Suma divizorilor Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.8 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("sumdiv.in");
ofstream g("sumdiv.out");
const int MOD = 9901;
int A, B, prod = 1;
void EuclidExtins(int a, int b, int &d, int &x, int &y)
{
    int x1 = 0, y1 = 1;
    x = 1, y = 0;
    while(b != 0)
    {
        int q = a / b;
        int r = a % b;
        a = b;
        b = r;
        int x0 = x - x1 * q;
        int y0 = y - y1 * q;
        x = x1;
        y = y1;
        x1 = x0;
        y1 = y0;
    }
    d = a;
}

int inversmod(int a, int P)
{
    int d, x, y;
    EuclidExtins(a, P, d, x, y);
    x %= P;
    if(x < 0)x += P;
    return x;
}

int aranjmod(int n, int k, int P)
{
    long long nr = 1;
    for(int i = 0; i < k; i++)
    {
        nr *= (n - i) % P;
        nr %= P;
    }
    return nr;
}

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

void calc(int p, int alfa)
{
    alfa *= B;
    p %= MOD;
    if(p != 0)
    {
        if(p == 1)
            prod = prod * (alfa + 1) % MOD;
        else
        {
            prod = prod * (putere(p, alfa + 1) - 1) % MOD;
            prod = prod * inversmod(p - 1, MOD) % MOD;
        }
    }
}

void divizori()
{
    for(int i = 2; i * i <= A; i++)
        if(A % i == 0)
        {
            int ex = 0;
            do
            {
                ex++;
                A /= i;
            }
            while(A % i == 0);
            calc(i, ex);
        }
    if(A > 1)
        calc(A, 1);
}

int main()
{
    f >> A >> B;
    divizori();
    g << prod;
    return 0;
}