Cod sursa(job #2126550)
Utilizator | Data | 9 februarie 2018 18:46:44 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int n,i,j,nr;
bool viz[2000010];
int main()
{
fin>>n;
for(i=2;i<=n;++i)
{
if(viz[i]==0)
{
++nr;
for(j=i+i;j<=n;j=j+i)
viz[j]=1;
}
}
fout<<nr;
return 0;
}