Cod sursa(job #756966)

Utilizator MciprianMMciprianM MciprianM Data 10 iunie 2012 20:01:31
Problema Suma divizorilor Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.99 kb
#include <fstream>

using namespace std;

long long put (long long a, long long b, long long mod) {
	if (a == 1)	return 1 % mod;
	if (b == 0)	return 1 % mod;
	if (b == 1)	return a % mod;
	long long temp = put (a, b >> 1, mod);
	temp = (temp * temp) % mod;
	if (b & 1)	temp = (temp * a) % mod;
	return temp;
}

int invers (int val, int coprim) {
	return put (val % coprim, coprim - 2, coprim);
}

int calcul_suma_progresie (int q, int n, int mod) {
	if (q % mod == 1) return (n + 1) % mod;
	else {
		return ((put (q, n + 1, mod) + 9900) * (invers (q - 1, mod))) % mod;
	}
}

int main () {
	int a, b, t, p, s = 1, mod = 9901;
	ifstream f ("sumdiv.in");
	ofstream g ("sumdiv.out");
	f >> a >> b;
	for (p = 2; p * p <= a; ++ p) {
		t = 0;
		while (a % p == 0) {
			a /= p;
			++ t;;
		}
		if (t > 0) {
			s = (s * calcul_suma_progresie (p, t * b, mod)) % mod;
		}
	}
	if (a > 1) {
		s = (s * calcul_suma_progresie (a, b, mod)) % mod;
	}
	g << s << endl;
	return 0;
}