Cod sursa(job #630513)

Utilizator bogdanrnRadu Bogdan Nicolae bogdanrn Data 5 noiembrie 2011 17:50:51
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
#include<iostream>
#include<fstream>
using namespace std;
int main ()
{
	ifstream f("ciur.in");
	ofstream g("ciur.out");
	int n,nr=0;
    f>>n;
	bool x[2000001];
	for (int i=2;i<=n;i++)
	{
		if (x[i]==0)
		{
			for (int j=i+i;j<=n;j+=i) {
			    x[j]=1;
			    }
			nr++;
		}
	}
	g<<nr;
	f.close(); g.close();
	return 0;
}