Cod sursa(job #293433)
Utilizator | Data | 1 aprilie 2009 20:41:04 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include<fstream.h>
#include<math.h>
long n,i,nr,j,ok;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int prim(long x)
{
ok=1;
for(j=2;j*j<=i;j++)
if(x%j==0)
ok=0;
return 0;
}
int main()
{
fin>>n;
for(i=2;i<=n;i++)
{
prim(i);
if(ok==1)
nr++;
}
fout<<nr;
return 0;
}