Cod sursa(job #708405)

Utilizator Roninsabau sabin nicolae cristian Ronin Data 6 martie 2012 19:41:55
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<stdio.h>
unsigned long v[200001]={1};
int main()
{
	long i,j,n,a=1;
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	scanf("%ld",&n);
	for(i=0;i<=n;i+=2)
	v[i]=0;
	v[1]=0;
	for(i=2;i<=n;i++)
	{
		if(v[i])
		{
		a++;
		for(j=2*v[i];j<=n;j+=v[i])
			v[j]=0;
		}
	}
	printf("%ld",a);
	return 0;
}