Cod sursa(job #871947)

Utilizator RusuDRusu Daniel RusuD Data 5 februarie 2013 16:39:50
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.3 kb
#include <fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
long n,nr=0,v[2000000],i,j;
int main()
{fin>>n;
 for(i=2;i<=n;i++)
  if(v[i]==0)
   {nr++;
    for(j=i+i;j<=n;j+=i)
     v[j]=1;
   }
 fout<<nr<<'\n';
 fin.close();
 fout.close();
 return 0;
}