Cod sursa(job #1105595)

Utilizator s1mpMihai Alexandru s1mp Data 11 februarie 2014 21:40:44
Problema Factorial Scor 5
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.33 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>

using namespace std;

long P;

long log(long X) {
	long l = 0;
	long p = 1;
	while (p*5 <= X) {
		p*=5;
		l++;
	}
	return l;
}

int main() {
	ifstream f("fact.in");
	ofstream g("fact.out");
	f>>P;
	long x = log(P*5);
	g<<P*5 - (x*(x-1)/2)*5;
	f.close();
	g.close();
	return 0;
}