Cod sursa(job #2663043)

Utilizator YusyBossFares Yusuf YusyBoss Data 25 octombrie 2020 10:50:25
Problema Suma divizorilor Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.58 kb
#include <iostream>
#include <stdio.h>
#define MOD 9901

using namespace std;

int prod;

void rid_put(int x, int put, int mod) {
  if (put == 0)
    return;
  if (put % 2 == 1)
    prod = (1ll * prod * x) % mod;
  x = (1ll * x * x) % mod;
  rid_put(x, put / 2, mod);
}

int sum_div(int a, int b) {
  int d, put, nr1, nr2, sol;
  sol = 1;
  for (d = 2; d * d <= a; d++) {
    put = 0;
    while (a % d == 0) {
      put++;
      a /= d;
    }
    if (put > 0) {
      put *= b;

      if (d % MOD != 1) {
        prod = 1;
        rid_put(d % MOD, put + 1, MOD);
        nr1 = (prod - 1 + MOD) % MOD;

        prod = 1;
        rid_put((d - 1 + MOD) % MOD, MOD - 2, MOD);
        nr2 = prod;

        sol = (1ll * sol * nr1) % MOD;
        sol = (1ll * sol * nr2) % MOD;
      }
      else
        sol = (1ll * sol * (put + 1)) % MOD;
    }
  }
  if (a > 1) {
    d = a;
    put = b;

    if (d % MOD != 1) {
        prod = 1;
        rid_put(d % MOD, put + 1, MOD);
        nr1 = (prod - 1 + MOD) % MOD;

        prod = 1;
        rid_put((d - 1 + MOD) % MOD, MOD - 2, MOD);
        nr2 = prod;

        sol = (1ll * sol * nr1) % MOD;
        sol = (1ll * sol * nr2) % MOD;
      }
    else
      sol = (1ll * sol * (put + 1)) % MOD;
  }

  return sol;
}

int main() {
  FILE *fin, *fout;
  int a, b;

  fin = fopen("sumdiv.in", "r");
  fscanf(fin, "%d%d", &a, &b);
  fclose( fin );

  fout = fopen("sumdiv.out", "w");
  if (a)
    fprintf(fout, "%d", sum_div(a, b));
  else
    fprintf(fout, "0");
  fclose( fout );
  return 0;
}