Cod sursa(job #381743)
Utilizator | Data | 11 ianuarie 2010 13:51:31 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.28 kb |
#include <fstream.h>
long n,c,nd,x,nr;
ifstream fin ("ciur.in");
ofstream fout ("ciur.out");
int main ()
{
fin>>n;
nr=n;
for (c=2;c<=n/2;c++)
{
nd=0;
for (x=2;x*x<=c;x++)
if (c%x==0)
nd++;
if (nd==0)
nr=nr-n/c+1;
}
fout<<nr;
return 0;
}