Cod sursa(job #671058)
Utilizator | Data | 30 ianuarie 2012 17:07:11 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include<cstdio>
using namespace std;
bool uz[2000005];
int nr, n;
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%d", &n);
for(int i=2;i<=n;++i)
if(!uz[i])
{
++nr;
for(int j=i+i;j<=n;j+=i)
uz[j]=1;
}
printf("%d\n",nr);
return 0;
}