Cod sursa(job #1040415)
| Utilizator | Data | 24 noiembrie 2013 15:08:40 | |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 100 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.28 kb |
#include <fstream>
using namespace std;
ifstream in ("ciur.in");
ofstream out ("ciur.out");
char v[2000005];
long long i,j,n,k;
int main()
{
in>>n;
for (i=2;i<=n;i++)
v[i]=1;
for(i=2;i<=n;i++)
if(v[i]==1){
k++;
for(j =2*i;j<=n;j+=i)
v[j]=0;
}
out<<k;
return 0;
}
