Cod sursa(job #406737)

Utilizator paul_gabryelPaul Buda paul_gabryel Data 1 martie 2010 19:16:53
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<cstdio>
using namespace std;
int c[2000015];
int main ()
{
	int n;
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	scanf("%d",&n);
	c[0]=c[1]=1;
	for(int i=2;i<=n;i++)
		for(int j=2*i;j<=n;j+=i)
			c[j]=1;
	int nrp=0;
	for(int i=2;i<=n;i++)
		if(c[i]==0)
			nrp++;
	printf("%d",nrp);
	return 0;
}