Cod sursa(job #247556)
Utilizator | Data | 23 ianuarie 2009 12:10:43 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 90 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.3 kb |
#include<fstream>
using namespace std;
ifstream f1 ("ciur.in");
ofstream f2 ("ciur.out");
int main()
{
int n,s,i,j;
char v[2000001];
f1>>n;
f1.close();
s=0;
for (i=2; i<=n; i++)
if (v[i]==0)
{
s++;
for (j=i*2; j<=n; j=j+i)
v[j]=1;
}
f2<<s;
f2.close();
return 0;}