Cod sursa(job #161046)
Utilizator | Data | 17 martie 2008 16:27:31 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include <stdio.h>
int n,nr,x,z,b[1010];
char a[2000100];
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%d",&n);
int i;
for (i=2; i<=n; ++i)
{
if (a[i]==0)
{
++nr;
x=i;
while (x+i<=n)
{
x+=i;
a[x]=1;
}
}
}
printf("%d\n",nr);
return 0;
}