Cod sursa(job #195225)
| Utilizator |  Procopliuc Adrian Procopliuc |
Data | 16 iunie 2008 23:46:37 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 30 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.34 kb |
# include <stdio.h>
# include <math.h>
long int i,n,k=1,j;
char a[2000010];
int main ()
{
freopen ("ciur.in","r",stdin);
freopen ("ciur.out","w",stdout);
scanf ("%li",&n);
for (i=1;i<=n;i++)
a[i]='0';
for (i=3;i<=n;i=i+2)
if (a[i]=='0')
{
k++;
if (i*i<n)
for (j=i*i;j<=n;j=j+i)
a[j]='1';
}
printf ("%li",k);
return 0;
}
