Cod sursa(job #163764)

Utilizator jupanu92Anonim jupanu92 Data 23 martie 2008 10:12:43
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.31 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
char x[640000];
int main()
{unsigned long int n,i,nr=0,j;

ifstream fin("ciur.in");
ofstream fout("ciur.out");

fin>>n;

for(i=2;i<=n;i++)
    if(x[i]==0)
	  {nr++;
	   for(j=i;j<=n;j=j+i)
	       x[j]=1;
	   }
fout<<nr;
fin.close();
fout.close();
return 0;
}