Cod sursa(job #743015)
| Utilizator |  Eduard Stoica eddy13579 |
Data | 2 mai 2012 20:36:21 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 100 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.28 kb |
#include<cstdio>
#include<cstring>
using namespace std;
char c[2000001];
int main()
{
freopen("ciur.in","r",stdin);freopen("ciur.out","w",stdout);
int n,i,j,s=1;
scanf("%d",&n);
for(i=3;i<=n;i+=2)
{
if(!c[i])
{
s++;
for(j=i+i;j<=n;j+=i)
c[j]=1;
}
}
printf("%d",s);
}