Cod sursa(job #161046)

Utilizator raduzerRadu Zernoveanu raduzer Data 17 martie 2008 16:27:31
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
#include <stdio.h>

int n,nr,x,z,b[1010];
char a[2000100];

int main()
{
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	scanf("%d",&n);
	int i;
	for (i=2; i<=n; ++i)
	{
		if (a[i]==0)
		{
			++nr;
			x=i;
			while (x+i<=n)
			{
				x+=i;
				a[x]=1;
			}
		}
	}
	printf("%d\n",nr);
	return 0;
}