Cod sursa(job #3164718)

Utilizator DariusHHanganu Darius DariusH Data 4 noiembrie 2023 10:17:51
Problema Suma divizorilor Scor 70
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.25 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("sumdiv.in");
ofstream fout("sumdiv.out");

#define MOD 9901

void euclid(int a, int b, int *d, int *x, int *y) {
    if(b == 0) {
        *d = a;
        *x = 1;
        *y = 0;
    }else{
        int x0, y0;
        euclid(b, a % b, d, &x0, &y0);
        *x = y0;
        *y = x0 - (a / b) * y0;
    }
}

int inversmodular(int a, int b) {
  int d, x, y;
  euclid(a, b, &d, &x, &y);
  while(x <= 0) {
    x += b;
  }
  return x;
}

long long int exp(long long int a, long long int b) {
  long long int result;
  result = 1;
  while(b > 0) {
    if(b % 2 == 1) {
      result = (result % MOD * a % MOD) % MOD;
    }
    a = (a % MOD * a % MOD) % MOD;
    b /= 2;
  }

  return result;
}

int main()
{
  long long int a, b, d, cnt, result, c;
  fin >> a >> b;
  d = 2;
  cnt = 0;
  result = 1;
  while(a > 1) {
    cnt = 0;
    while(a % d == 0) {
      ++cnt;
      a /= d;
    }

    if(cnt > 0) {
      cnt *= b;
      c = (exp(d, cnt + 1) - 1) % MOD;
      result = (result * (c * (inversmodular(d - 1, MOD) % MOD))) % MOD;
    }

    ++d;

    if(d * d > a && a > 1) {
      d = a;
    }
  }

  fout << result << "\n";

  return 0;
}