Cod sursa(job #168082)

Utilizator zalmanDanci Emanuel Sebastian zalman Data 30 martie 2008 18:22:53
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
#include<fstream.h>
int ciur[130000];
long n,k;
ifstream f("prim.in");
ofstream g("prim.out");
int main()
{
 f>>n;
for (int i=2;i<=n;++i)
    ciur[i]=1;
for (i=2;i*i<=n;++i)
    if (ciur[i])
	for (intj=i*i;j<=n;j+=i)
	    ciur[j] = 0;
   for(i=2;i<=n;i++)
    if(ciur[i])
     k++;
     g<<k;

   f.close();
   g.close();
   return 0;
}