Cod sursa(job #659053)
| Utilizator | Data | 9 ianuarie 2012 22:55:47 | |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.31 kb |
#include <fstream>
using namespace std;
int p[2000001],i,j,nr,n;
int main ()
{
ifstream f ("ciur.in");
ofstream g ("ciur.out");
f >>n;
for (i=2; i<=n; i++)
p[i]=1;
for (i=2; i<=n; i++)
if (p[i])
{
nr++;
for (j=i+i; j<=n; j+=i)
p[j]=0;
}
printf("%d\n", nr);
return 0;
}
