Cod sursa(job #369387)
Utilizator | Pop Razvan flashthd | Data | 28 noiembrie 2009 12:09:50 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.75 kb |
#include <fstream>
#include <math.h>
using namespace std;
int main()
{
//toate numerele prime mai mici decat n\
int n,k,i,prim,contor=0,radical;
ifstream fin("ciur.in");
fin>>n;
fin.close();
for(k=2;k<=n;k++)
{
radical=(int)sqrt(k);
prim=1;
for(i=2;i<=radical;i++)
if (k%i==0)
{ prim=0;break;}
if (prim==1) contor++;
}
ofstream fout("ciur.out");
fout<<contor;
fout.close();
return 0;
}