Cod sursa(job #527579)

Utilizator maooBompa Mario maoo Data 31 ianuarie 2011 21:48:33
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
#include<cstdio>

using namespace std;
int v[2000010],nr,i,j,n;
int main()
{
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	scanf("%d",&n);
	for(i=3;i<=n;i+=2)
	{
		if(!v[i])
		{
			nr++;
			for(j=3*i;j<=n;j+=2*i)
				v[j]=1;
		}
	}
	nr++;
	printf("%d",nr);
}