Cod sursa(job #790080)
Utilizator | Data | 20 septembrie 2012 12:43:19 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int n,i,j,k;
char v[2000001];
int main()
{
f>>n;
for (i=2;i<=n;i++)
if (v[i]==0)
//{
for (j=2*i;j<=n;j=j+i)
v[j]=1;
//k++;
//}
for (i=2;i<=n;i++)
if (v[i]==0) k++;
g<<k;
f.close();
g.close();
return 0;
}