Cod sursa(job #527579)
Utilizator | Data | 31 ianuarie 2011 21:48:33 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include<cstdio>
using namespace std;
int v[2000010],nr,i,j,n;
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%d",&n);
for(i=3;i<=n;i+=2)
{
if(!v[i])
{
nr++;
for(j=3*i;j<=n;j+=2*i)
v[j]=1;
}
}
nr++;
printf("%d",nr);
}