Cod sursa(job #756938)

Utilizator MciprianMMciprianM MciprianM Data 10 iunie 2012 19:17:21
Problema Suma divizorilor Scor 80
Compilator cpp Status done
Runda Remember Mihai Pătrașcu Marime 1 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 prim) {
	return put (val, prim - 2, prim);
}

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 = 1;
		while (a % p == 0) {
			a /= p;
			t *= p;
		}
		if (t > 1) {
			t = t % mod;
			t = ((p % mod) * put (t, b, mod)) % mod;
			-- t;
			if (t < 0)	 t += mod;
			s = (s * t) % mod;
			s = (s * invers (p - 1, mod)) % mod;
		}
	}
	if (a > 1) {
		t = a;
		t = t % mod;
		t = ((a % mod) * put (t, b, mod)) % mod;
		-- t;
		if (t < 0)	 t += mod;
		s = (s * t) % mod;
		s = (s * invers (a - 1, mod)) % mod;
	}
	g << s << endl;
	return 0;
}