Cod sursa(job #588356)

Utilizator lily3Moldovan Liliana lily3 Data 7 mai 2011 19:01:28
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
#include<fstream>
using namespace std;

int i,n,a[2000001];
unsigned long nr=0;
unsigned long ciur()
{
	int i,j;
	for(i=2;i<=n;i++)
	{
		if(!a[i])
		{
			nr++;
			for(j=i+i;j<=n;j+=i)
				a[j]=1;
		}
	}
	return nr;
}
int main()
{
	ifstream f("ciur.in");
	ofstream g("ciur.out");
	f>>n;
	g<<ciur();
		return 0;
}